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To acccrrti'OJiY BulUiJv?^ 10 .ThomPs SubdiviMnr^. Hn.>i-nk, JKyisum. AiLckljind Land District ■- 




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To acccmpafi Y BuUeJui A^ fC, Thairt^s Subdivision.. Bcutrakl IKvisi^ri: AujcklxmA Zand JhsUict 




AMES MACKINTOSH BELL 



PLAN OF THE 

— THAMES GOLDFIELD. N.Z . — 

SHOWING MINING AREAS. MAIN REEFS, AND PRINCIPAL UNDERGROUND WORKINGS ,., 
THE HANGING- WALL SIDE OF THE MOANATAIARl FAULT, ALSO THE COMPUTED POSITIONS 
OF THE MAIN REEFS, MOANATAIAR l FAULT, AND BEA CH SLIDE' AT THE lOOO' LEVEL. 

Notes. Datum is High Wafer Mark. 

Reefs proved by mining colored red. 

Moanataiari Fault. Beach Slide, and reefs computed to lOOO' level colored yellow . 

In the main this map is a replica of that compiled by E F.Adams, ME.LicSurv. Thames, and pub- 
-lished in Mines report C-3 1907 '^ 



fin Auth^rttf ; Joint Uaolia^, Oovernment Prlntar. 



Posillon of en orabeannij to/>a('') 

as su^gestad by results of boring 



SECTION ON LINE F G 



Dr-nv.-n fry Q E Harris .^T^m=^ !3!0 _ 



Tv accompany Bulleiuxl^ W.Tliiunes Subdivision,. EruiraJd I>vfisu?rt . Auckland LcmJ Distrjct 




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To acccmpaity BuHelui.^ W.TJignies Subdivision .}Jn,^rii}.-i Di-visUTf . Airkht7ul ZmiJ Disb-ict 




fls Awthorlli , John Maokay. <3ovinimtnl Print 



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\ Andesitic snd dac'itic fSovrs snd breccias 

•dispos't'iort rery irregular 






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Section on Line DE 



GEOLOGICAL SECTIONS 
SPECIAL AREA 

THAMES COLDFIELD, N.Z 



-Natural Sciile - 



By AuthorUy : Jahn Mackay.Gevinaiunt Prinin, 




Bulhtin Xo. 70.] 



Pakohajfic View of Thamks 



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'^epavUnent /of /|#^ ^»\ of "gilhtes 



NEW ZEALAND GEOLOGICAL SURVEY 

(J. M. BELL, Director.) 



BULLETIN No. 10 (New Series). 






THE GEOLOGY 



OF THE 



THAMES SUBDIVISION 



HAURAKI, AUCKLAND. 



COLIN FRASER. 



ISSUED UNDER THE AUTHORITY OF THE HON. R. McKENZIE, MINISTER OF MINES. 




WELLINGTON. 

BY AUTHORITY: JOHN MACKAY, GOVERNMENT PRINTER. 

1910. 



Ill 



LETTEE OF TRANSMITTAL. 



Geological Survey Office, 

Wellington, 1st January, 1910. 

Sir,— 

I have the honour to submit herewith Bulletin No. 10 (new series) 

of the New Zealand Geological Survey. 

This bulletin covers a report on the geology of the Thames Subdivision, 
Hauraki, Auckland, by Mr. Colin Eraser, Mining Geologist. 

The volume comprises 136 pages of letterpress. It contains ten maps and 
sections, and is illustrated by twenty-three plates and diagrams. 

I have the honour to be, 

Sir, 

Voui- ol)edieut servant, 

J. M. BELL, 

Director. 
Hon. K. McKenzie, 

Minister of Mines, 

Wellington. 



CONTENTS. 



Letter of Transmittal 



I'age 
iii 



Chapter I. — Introductory and General Information. 



General Description of the Area 
General Geological Features 
Aoknowledgmeata 



Page 
1 
2 
3 



Officers connected with the Field-work 
Literature 



Page 
3 
4 



Chapter II. — History and Technology of Mining on the Thames Goi.dfield. 



History of Mining Development 
Mineral Production 



8 
10 



Mining and Treatment of Ores 
Labour and Financial Conditions 



11 
13 



Geology 



Chapter III. — Outunb of the Gboix)oy and Physiography of the Area. 
. . 15 j Physiography 



16 



Chapter IV. — General Geology. 



Table of Formations 

Pre-Jurassic and Jurassic Stratified Rooks 
(1.) The Tokatea Hill Series 
(2.) The Manaia Hill Series 
Igneous Rocks 

(1.) Tertiary Volcanic Rocks of the " First 
Period " 
General Statement 
Age 

Distribution 
Petrology 

(2.) Tertiary Volcanic Rocks of the " Second 
Period " (Beeson's Island Series) 
General Statement 
Age 

Distribution 

Structure and Petrology . . 
(3.) Tertiary Volcanic Rocks of the " Third 
Period" 



19 Igneous Rocks — continued. 

20 (3.) Tertiary Volcanic Rocks, &c. — continued. 

20 General Statement . . . . 2fi 

21 Age .. .. .. ..20 

22 Distribution . . . . 20 
Structure and Petrology . . . . 27 

22 (4.) Intrusive Rocks of Various Periods .. 27 

22 (Jeneral Statement .. ..27 

23 Age .. .. .. ..28 

23 Distribution and Petrology . . 28 

23 Loo.selv Consolidated and I'nconsolidatcd 

Debris . . . . . . . . 29 

25 (a.) Late Pliocene or Pleistocene Deposits 29 

25 (b.) Recent Deposits .. .. ..29 

25 Regional Earth-movements and Faulting . . 30 

25 The Moanataiari Fault . . . . 30 

25 i The Collarbone Fault . . . . . . 31 

The Beach " Slide ' or Fault . . . . 31 

26 I Minor Faults . . . . . . . . 32 



Chapter V. — Mineral Veins and Conditions in Mineralised Areas. 

Periods of Mineralisation . . 

The Vein Fissures 

The Mineralising Agents . . 

Rock-alteration connected with Mineralisation 

Mineralogy of the Vein-minerals 

Non-metallic Minerals . . 

Metallic Minerals 



33 


Structure of the Vein-material 


.. 41 


33 


Oxidation 


.. 42 


34 


The Ore-deposits 


.. 42 


34 
36 
36 
37 


Underground Temperatures 
Underground Gases 
Underground Water 


.. 45 
.. 47 
.. 48 



V] 



Chapter VI. — ^Detailed Descriptions of Mining Areas and Mining Claims. 



M;iiuii;i Viilley 

Waikawiiu Valley . . . . 

Te Mata Valley . . 

Tapu Valley 

The Sheridan and .Adjoining Claims 

Mclsaac's Old Claim 

Mahara Royal Area 
Diehard, Whalebone, nnd Otnintutu Valleys. . 
Pnhoi Valley 

Mount Zeehan Claim 
Waiomo Valley . . 

Monowai Claims 

Colorado (Old Comstoek) Claim . . 

Paroquet Claim . . 

Golden Gem Claim 
Puru Valley 

Puru Consolidated Claim 

Puru Big Reefs Claim . . 
Otohi Valley 
Tararu Valley (above Ohio Creek Junction) . . 

Eclipse Claim . . 

Scandinavian Claim 

Chicago Claim 

Temple Bar Claim 

Argosy Claim . . 
Kaimarama V^alley . . . . 

Waiwawa and Ounaroa Valley-s 
Kauaeranga Valley 

Otaniii Consols Claim . . 

Tne Cinnabar Occurrences of Mangakirikiri 
Kirikii i Valley . . 
Wharehoe and Matatoki Valleys 
Puriri Valley 
Omahu Valley 

The Mining - area and Mining Claims at and 
near the Town of Thames (Thames Special 
Area) 

Boundaries of the Special Area . . 

The Oldest Rocks 

The Vein-bearing Rocks 

(ft.) The Andesitic Flow and Breccia Com- 
i>lex 



Page. 
50 
51 
51 
52 
52 
53 
54 
54 
55 
55 
56 
50 
59 
59 
60 
60 
60 
61 
61 
01 
61 
62 
63 
63 
63 
63 
64 
04 
65 
65 
66 
66 
66 
67 



67 
67 
68 
68 

t>8 



The Mining -area and Mining Claims at and 

near the Town of Thames (Thames Special 

Area) — continued. 
The Vein-bearing Rocks — continued. 

(b.) Non-brecciated Andesite (the '" Pre 
mier " Flow) . . 
Structural Breaks 
The Gold-bearing Reefs 
Day Dawn and Norfolk Claim 
Watchman Claim 
Di.xon's Consolidated ( 'laini 
Sylvia Claim . . 
Bonanza Claim 
Waitangi Claim 
Old Alburnia Claim 
Jloanataiari Extended Claim (Hidden Trea 

sure) 
Reliance Claim 
Thames Claim ... 

West Coast Claim 
Golden Drop Claim 
Magnet Claim 
Arrindell Claim 
Halcyon Claim 
Southern Queen Claim . . 
The Mining Claims of Una Hill and Vicin 

Lone Hand Section of .May Queen ( 'la 

May Queen Extended Claim 

New Una Claim 

New Occidental Claim 

New Dart Claim 

Anchor or Ethel Reefs Area 

Other Claims 
Kuranui Claim 
Kuranui-Caledcnian Claim 
New Moanataiari Claim 
Waiotahi Claim 
Victoria Claim 
Saxon Claim . . 
May Queen ( 'laim 
Shortland Flat Claim . . 
A'anguard Claim 
Thames Deep-levels Consolidated Claim 



Tage 



69 
70 
70 
71 
74 
75 
75 
77 
78 
81 

85 
85 
85 
87 
87 
87 
88 
89 
90 
90 
92 
92 
92 
93 
93 
94 
95 
95 
96 
99 
103 
106 
108 
110 
114 
ll.-> 
11.-) 



Chapter VII. — Summary of the Mineral Resources or the Thames Subdivision 

16 



The Future Prospects of Gold-Silver Mining. . 
(1.) The Future Pro.spects of Mining-areas 

outside the Thames Special Area . . 117 
(2.) The Future Prospects of the Thames 

Special Area .. .. ..118 

(a.) The Upland Block .. ..119 

(b.) The Central Block . . . . 120 

(f.) The Seaward Block . . . . 123 



.Metalliferous Deposits other than Gold-Silver 
Veins .. .. .. ..124 

Stones for Building and Macadamising Pur- 
poses . . . . . . . . 124 

Coal .. .. .. .. ..124 



Appendices. — 

List of Elevations of the Principal Mine-workings of the Thames Special Area . . . . . . 125 

Table of Geological Formations compared with those of Pievious Writers . . . . (facing) 128 



Index 



129 



Vll 



LIST OF ILLUSTRATIONS 



Panoramic View of Thames . . . . . . . . . . . . . . Frontispiece. 

Facing page 
The Table Mountain, as viewed from Trigonometrical Station 97 (Taurauikau) on Table Mountain 

Range . . . , . . . . . . . . . . . . . . . . l(i 

Andesite Dyke intersecting Beeson's Island Volcanics, Kauaeranga Valley, Thames . . . . 2() 

The Moanataiari Fault-scarp, Thames. View looking Southward from Spur between Shellback 

Creek and ShotoVer Creek . . . . . . . . . . . . . . . . 30 

Andesitic Breccia-agglomerate (Beeson's Island Series) overlain by a Flow Andesite, Tapu \'alley, 

Thames . . . . . . . . . . . . . . . . . . . . 54 

Kauaeranga Valley, Thames . . . . . . . . . . . . . . . . (54 

Moanataiari Fault (Slickensided Foot-wall) laid bare by Denudation, Waiotahi Creek X'alley, Thames 70 

Shellback Creek Valley, Thames, showing Locality of the \Vaitangi Gold- mining Company's 

Workings . . . . . . .... . . . . . . . . . . 80 

Waiotahi Mine, W'aiotahi Creek Valley, Thanus . . . . . . . . . . . . 102 

Thames- Hauraki Shaft and Pumping-station, Thames ,, ,, ,, ,. .. IJO" 



LIST OF MAPS AND SECTIONS. 



New Zealand, showing Land Districts and Divisions 

Hauraki Division, showing Survey Districts and Area geologically surveyed 

Map showing Mining Claims (existing or abandoned) in Vicinity of Thames 

Geological Map of Hastings Survey Di.strict (with Section) 

Geological Map of Thames Survey District (with Section) 

Geological Maj) of Waihou Survey District 

Topographical and Geological Map of the Special Area of Thames GoldHeld, New Zealand 

Geological Sections, Special Area of Thames Goldficld, New Zealand 

Map of Thames Special Area, showing Boundaries of the various .Mining Claims as at the 
30th April, 1910 (Transparency to accompany Topographical and Geological Map) 

Plan of Thames (joldfield. New Zealand, showing the Mining Areas, Main Reefs, and Principal 
Underground Workings in the Hanging-«all Side of the Moanataiari Fault : also the Com 
puted positions of the Main Reefs, Moanataiari Fault, and Beach " Slide " at the 1,000 ft 
Level . . 



Facing page 
viii 

viii 

66 

In portfolio. 



Vlll 



LIST OF DIAGRAMS. 



Diagram showing the Total \'alue of the (Jold-Silver Bullion from Mines in the Thames County, New 
Zealand, for the Years 1867-1908 (Plate) 

Plan showing the Principal Auriferous Area of the Lower Portion of the Tapu Valley . . 

Map of Principal Mining Area in the Waiomo and Puhoi Valleys 

Section Monowai Reef . . 

Sketch of Waitangi Vein, showing Bend and Approximate Position of Branch of Moanataiari Fault 

Vertical Section on Line of Old Alburnia Company's Main Rise 

Ore-shoots of the Golden Age and Reuben Parr Reefs (Plate) 

Sketch-plan of the Locality of the Caledonian - Golden Crown Bonanza (Cox) . . 

Plan and Sections of the Junction of the Hanging-wall Leader with No. 1 Reef, Golden Crown Mine 
(Cox) 

Plan and Section of Nos. 1 and 2 Reefs, Kurantii-Caledonian Mine 

Sketch-plan and Section of the Locality of the Bonanaza of the Moanataiari No. 9 Reef . . 

Locality of the Cambria Bonanza, No. 3 Level, Cambria Workings 

Plan and Section of the Waiotahi Bonanza, Waiotahi Mine, Thames (Plate) 



Facing page 

10 

Page 

53 



56 

57 

79 

83 
Facing page 
84 
Page 
97 

98 

99 

101 

102 

Facing page 
105 




• OOO.'^OS- J<« 



By Authority : John Mtinkay^ Govemmtnt PrinUr, 




•• Aulhtrltn Jthii Mmoliat. Oovrnrntit ^rlnUr. 



yoo-e lo.sje 



BULLETIN No. 10 (NEW SERIES). 



THE GEOLOGY 



OF THE 



THAMES SUBDIVISION, 

H A U R A K I, AUCKLAND. 



CHAPTER I. 



INTRODUCTORY AND GENERAL INFORMATION. 





V&iic 




Page 


General Description of the Area 


1 


Officers connected with the Field-work . 


. 3 


General Geological Features . . 


■> 


Literature 


,. 4 


Acknowledgments 


.. 3 







(teneral Description op the Area. 
The Thames Subdivision of Hauraki, the area upon which the present report is based, con- 
stitutes the south-western portion of the Cape Colville Pcninsuhi and a contiguous pa it 
of the southern mainland from which this peninsula springs. The northern or peninsula 
portion of the area embraces the country drained by all the streams entering the Firth of 
Thames between Deadman's Point and the mouth of the Thames River, also the major part 
of the region drained by the Waiwawa, Ounaroa, and Kaimarama streams flowing into the 
Whitianga Estuary on the eastern coast-line. The mainland area includes about 179 square 
miles of the broad flood-plain of the Thames and Piako rivers, extending .southward to and 
a little beyond Paeroa, also an irregular strip of the western slopes of the mountainous country 
— an extension of the peninsula mass — bordering this plain to the eastward. 

The subdivision compri.scs the survey districts of Hastings, Thames, and Waihou, and 
covers an area of 385 square miles. 

The portion of the peninsula north of that under review i.s the Coromandel Subdivision, 
described in Bulletin No. 4 (New Series) of this survey. 

The country, apart from the Thames-Piako or Hauraki Plains, is for the most part hilly, 
and even mountainous. The dominant physiographic feature is the Cape Colville Range, 
which forms the backbone of the peninsula and of the elevated country extending further 
southward. The major peaks of this range rise to heights varying from 2,000 ft. to 2,700 ft. 
The hill country extends westward from this water-parting to, or almost to, the shore-line of 

1 — Thames. 



2 

the Fiitli oi Thames and eastward to and l)eyond the limits of the subdivision. The topo- 
cfiaphy is that characteristic of a deeply dissected volcanic area of medium elevation. 

T'he land-surface in its natural state is clothed with a luxuriant growth of forest vegeta- 
tion which, at the lower elevations, is almost subtropical in aspect. As might be expected, 
a gradual change in character is noticeable as one ascends from the coast-hne to the summits 
of the higher ranges, but even at these elevations plant-hfe is fairly proUfic. 

The climate, as the character of the flora would suggest, is decidedly temperate. The 
mean annual temperature is approximately 57° Fahr., and the greatest range, as indicated 
by mean temperatures of the hottest and the coldest months, is only 15° Fahr. Rain falls on 
from 155 to 165 days in the year, the mean annual rainfall being about 49 in. Snow, except 
as verj^ light and infrequent falls on the crests of the higher ranges, is unknown in the area. 

Settlement is principally confined to the small areas of low - Ijdng country — the fans 
of streams draining the peninsula and entering the Firth of Thames — and also to the more 
extensive Hauraki Plains further southward. 

Thames, a typical goldfield town — population, 5,627 at census of 1906 — is the chief centre 
of population and the principal port of the district. It is built upon the narrow strip of coastal 
plain fringing the hilly mining country and bordering the sheltered waters of the Firth of 
Thames. Although the port is workable only by shallow-draught vessels at suitable states 
of the tide, the Thames, as a goldfield's centre, is favourably situated. The town is within 
four hours' steam of Auckland, the provincial metropolis, and is also connected by rail, a 
seven hours' journey, with the same commercial centre, and en route with the agricultural 
and colHery districts of the Waikato ; it is favoured with a very good water-supply, and, as 
already indicated, enjoys an equable and healthy climate. 

In addition to mining, the principal industry, Thames owes much to the fact that there 
is established in the town two of the best-equipped iron-foundries and engineering-works in 
the Dominion. The town, as might be expected, draws a good deal of trade from the agri- 
cultural districts of the lower Thames Valley and elsewhere, and is also exporting fish to the 
value of some £12,000 per annum. 

The town and river-port of Paeroa — population 1,837* — hes eighteen miles southward 
of Thames, on the railway-line traversing the plains, and close to the right bank of the Thames 
River. It is essentially an agricultural and distributing centre, and, although included partly 
within the hmits of the subdivision, is more closely associated with the goldfield centres of 
Waihi and Karangahake, in the Tairua-Waihi Subdivision. 

Minor settlements are numerous. Kopu and Turua are sawmilling and timber-shipping 
centres on the Thames River, the timber — white-pine (kahikatea) — being derived from the 
forests of the plains through which the river meanders. Puriri and Hikutaia, small villages 
dependent on agriculture, he near the eastern margin of the plains, each in the vicinity 
of the debouchure from the hilly country of tributaries of the Thames River. Puru, 
Waiomo, Tapu, and Waikawau, on the picturesque western coast-Une of the peninsula, are 
small agricultural or mining settlements, through which passes the Thames-Coromandel coach- 
road. 

The total European population of the area constituting the Thames Subdivision is between 
nine and ten thousandf, while the remnant of what were formerly several powerful Maori 
tribes numbers about one thousand. 

General Geological Features. 

The prevailing rocks of the district are volcanic — andesites and rhyolites, referable to 
three distinct periods of Tertiary eruptive activity 

* Census of 1906. f The actual figures cannot be given, as the boundaries of the subdivision are 

independent of county boundaries. 



This volcanic complex rests upon, or breaks througli, an irregularly worn-down floor 
of folded and indurated Jurassic and pre-Jurassic sedimentaries. These basement sedi- 
mentaries over the greater part of the area lie below the datum line of sea-level. 

Intrusive rocks ramify throughout the eroded sedimentaries of certahi localities, and form 
the bold flat-topped Table Mountain, breaking through the dissected volcanic complex in the 
central part of the peninsula. Elsewhere they are inconspicuous. 

Crateriform hollows and other such structures, so conspicuous in certain areas of recent 
vulcanism, have here been entirely obliterated by agencies of subaerial erosion. 

A marked feature of the district is the widespread alteration of the volcanic rocks by 
hydrothermal action. Such alteration is most pronounced in connection with the older 
andesitic rocks in all the vein-bearing areas, the resultant rock assuming a propylitic facies. 

The subdivision owes its importance as a mining area exclusively to the occurrence of 
gold-silver quartz veins. These veins vary from mere thread-like partings to strong well- 
defined reefs, and their ore-shoots are generally of the bonanza type. Many of the bonanzas 
have proved of extraordinary richness, and, as is the general rule in veins of this type, local 
enlargements, faults, cross-courses, cross-veins, and muieralised bands, as well as the character 
of the wall-rock, have all exercised an important influence on the localisation of the ore-shoots. 
Most of these shoots also appear to show a considerable dependence on depth below the existing 
land-surface, since, irrespective of the elevations of the outcrops of the veins, the upper zone, 
extending to a depth of from 400 ft. to 500 ft., has proved much the more productive. It is 
believed by the writer that the principal veins at the Town of Thames occur in the near vicinity 
of the vent of an ancient volcano. 

The Thames, in common with the whole Hauraki area, presents many striking resemblances 
to the Washoe. Cripple Creek, and Tonapah mining districts of the United States of America 
and to the ancient mining field of the Hungarian province of Transylvania, in Europe. 



Acknowledgments. 

The writer takes pleasure in acknowledging his appreciation of the facilities afforded him 
in his mine-examinations by each and all of the mine-managers of Thames. To the same 
gentlemen, to the various mining secretaries, and to many others, particularly Mr. E. ¥. Adams, 
mining engineer and licensed surveyor, and Mr. W. H. Baker, Director of the Thames School 
of Mines, thanks is here formally tendered for much valuable information connected with 
mining operations of the past and for the use of many plans and records. 

To Dr. J. S. Maclaurin, Dominion Analyst, and his staff, all the chemical analyses quoted 
in this bulletin, except where mentioned to the contrary, are referable, and for the expedi- 
tious manner in which the various reports were furnished the writer is indebted. 

Officers connected with the Field-work. 

The field- examinations upon which this report is based have extended over a period 
totalling some twenty months. 

The writer had associated with him, for periods of one month and four months respec- 
tively, Mr. J. H. Adams and Mr. J. A. Bartrum, both formerly Assistant Geologists of the 
Survey. Dr. .1. M. Bell, Director of the Geological Survey, visited the Thames during the 
progress of the work, and spent a month in making a general surface reconnaissance of the 
mining centre with the writer, and also detailed investigations in the Day Dawn and Norfolk 
Mine, Tararu Creek. In these investigations at Tararu he was assisted by Mr. W. H. Baker. 
Mr. L. E. Autridge, of Thames, who possesses a good general knowledge of the various 
mines of the subdivision, and is a capable photographer, formed one of the temporary 
field-party. 

1 '—Thames. 



Literature. 
Since the date of tlie earliest gold-discoveries many reports and notices dealing with 
the geology and the mining industry of the Thames have appeared. The following list of 
authors and their publications may he considered fairly complete : — 
The abbreviations used are- 
Rep. G.S. : Reports of the Geological Survey of New Zealand. 
Trans. : Transactions of the New Zealand Institute. 
Q.J. G.S. : Quarterly Journal of Geological Society, London. 

C.-3. D.-18, &c. : A capital letter followed by a number refers to a New Zealand 
parliamentary paper. 
1863. " Gold Discoveries at Thames and Waikato." D.-18. 
1867. Hutton, F. W. : " Geological Report on the Thames Goldfield."' Rep. G.S., vol. iii, 

1867. 
1869. A.-17, B.-15, and L.C. p. 39. Map of the Thames, L.C. p. 42. 

1869. Hutton, F. W. : " Second Report on the Thames Goldfield." Rep. G.S., vol. v, 1869. 
1869. Hector, James : " Mining in New Zealand." (Abstract of lectures dehvered at the 

Colonial Museum.) Trans, ii, p. 361. 
1869. Hector, James : " Notes on Rocks and Minerals mentioned in Captain Button's Report 
on Thames Goldfield." Rep. G.S., 1869, p. 39. 

1869. " Gold Returns and Imports at the Thames." D.-7, 1869. 

1870. Hutton, F. W. : " On the Geology of Coromandel." Rep. G.S., vol. \± p. 2. 1871. 
1870. Hutton, F. W. : " Report on the Caledonian Mine, Thames Goldfield." Rep. G.S., 

vol. vi, p. 146, 1871. 
1870. Hector, James : " On the Geology of the Cape Colville District." Rep. G.S., vol. vi, 
p. 88, 1871. 

1870. Skey, Wilham : " Notes on the Processes in Use in the Thames Mining District for 

the Extraction of Gold from the Matrix." Rep. G.S., vol. vi, p. 70, 1871. 

1871. Davis, E. H. : " Notes on the Thames Goldfield." Rep. G.S., vol. vi, p. 56, 1871. 

(Appendix by W. Skey, pp. 84-85 same volume.) 
1871. " Thames Water-supply." D.-8 and D.-8a. 

1871. "Maps of Thames." D.-8, 1871. 

1872. Hutton, F. W. : " Report on Northern Coalfields " (includes coals of Hauraki). Rep. 

G.S., 1872. 
1872. " Maps of Thames." D.-3, 1872. 
1872. " Thames Water-supply." D.-3, p. 18. 

1872. G.^A. 

1873. Hutton, F. W. : " Geological Structure of the Thames Goldfield." Trans., vi, p. 272. 

1874. " Machinery on Thames." Report of Commission. H.-6, 1874. 

1877. Black, G. : " Notes on the Deposit in the Shaft of the Pumping Association (Thames)." 
.Trans., x, p. 456. 

1880. Smith, S. Percy : " On some Indications of Changes in the Level of the Coast-line in 

the Northern Part of the North Island." Trans., xiii, p. 398. 

1881. Cox, S. H. : " North Auckland District, including Thames, Coromandel, Island of 

Kawau, and Drury Coalfield." Rep. G.S., vol. xiv, pp. 17-41, 1881. 
1881. Cox, S. H. : " Notes on the Mineralogy of New Zealand." Trans., xiv, pp. 418-450. 

1881. Campbell, W. D. : " Notes on a Pseudomorphous Form of Gold (Thames)." Trans.. 

xiv, p. 457. 

1882. Pond, J. A. : " On the Occurrence of Platinum in Quartz Lodes at Thames Goldfield." 

Trans., xv, p. 419. 
1882. Cox, S. H. : " Goldfields of Cape Colville Peninsula." Rep. G.S., vol. xv, pp. 4-51, 
1882. 



5 

1882. Cox, S. H. : " Notes on the Mineralogy of New Zealand." Trans., xv, p. 361. 

1882. Hector, James : " Cape Colville District." Rep. G.S. (Progress Report), 1882. 

1883. Cox, S. H. : " On the Occurrence of some new Minerals in New Zealand." (Tellurides 

from Karangahake and Te Aroha.) Trans., xvi, p. 448. 

1883. Bramhall, H. : " The Mineral Resources of New Zealand." Trans. Liverpool Geo- 
logical Assn. 

1883. McKay, A. : " On the Geology of the Cabbage Bay District, Cape Colville Peninsula." 
Rep. G.S., vol. xvii, 1883, p. 192. 

1887. Galvin. P. : " Handbook of New Zealand Mines." (Preface by Hon. W. J. M. Larnach.) 

1887. Gordon, H. A. : " North Island Mining generally." Mines Report, p. 18, 1887. 

1887. Gordon, H. A. : " Treatment of Gold and Silver Ores." Mines Report, p. 58, 1887. 

1887. Pond, J. A. : " Minerals of the Cape Colville Peninsula." Mines Report, p. 56, 1887. 

1887. Hutton, F. W. : " On the Rocks of the Hauraki Goldticld." Aust. Assn. Adv. Science, 
vol. i, 1887. 

1887. Skey, \Vm., and McKay, A. : " Gold : Its Formation in our Reefs ; and Notes of some 
Newly Discovered Reactions." Aust. Assn. Adv. Science, vol. i, p. 155. 

1889. Hutton, F. W. : " The Eruptive Rocks of New Zealand." Journ. Roy. Soc. N.S.W., 

vol. xxiii. p. 102. 

1890. Hii'usler. Rudolf : " On the Microscopic Structure of the Ohincniuri (iold." (Notes 

on Thames.) Trans., xxiii, p. 335. 

1891. Park. James : ' On the Occurrence of Native Zinc at Hape Creek, Thames." Trans., 

xxiv, p. 384. 

1891. Hutton. F. W. : " Source of Gold at the Thames." N.Z. Journal of Science, vol. iii, 

1891. 

1892. Hector, James : " Minerals of New Zealand." Rep. G.S., vol. xxi, 1892 (Appendix). 

1893. Park, James : " On the Occurrence of some Rare Minerals in New Zealand." Trans., 

.xxvi p. 365. 
1893. Cussen, Lawrence : " Notes on the Piako and Waikato River Basins." 
1893. " Electrical Power for Mining Machinery at Kuaotunu and Thames : Report on the 

Practicability of usinji." C.-4, 1893. 

1893. " Crushing Plants at Thames." C.-3, 1893, p. 56 (Gordon). 

1894. Murray, R. A. F. : " Report on Deep Quartz-mining in New Zealand." C.-6, 1894. 
1894. Park, James : " Geological Resources and Future Prospects of the Thames Goldfield." 

C.-3, 1894, p. 52. 

1894. Hector, James : " The Thames Goldfield." Rep. (J.S. (Progress), vol. xxii. 1894. 

1895. Cadell, H. M. : " Gold-mining in th-i Hauraki District." Trans. Fed. Inst. Min. Eng., 

vol. i, 1895. (E.vtract in C.-3, 1896, p. 81.) 

1896. Baker, W. H. : " Plan and Section showing Relative Positions and Depths of Shafts 

at Thames." C.-3, 1896, p. 66. 

1896. Campbell, Joseph : " The Goldfields of the Hauraki Peninsula." Trans. North of Eng. 

Inst. Min. & Mech. Eng., 1896. 

1897. McKay, A. : " Report on the Geology of the Cape Colville Peninsula, Auckland." 

C.-9, 1897. (Editorial on same, N.Z. Mines Record, vol. i, p. 278.) 
1897. Park, James : " The Geology and Veins of the Hauraki Goldfield." Trans. N.Z. Inst. 

Min. Eng., 1897. (Extract N.Z. Mines Record, vol. i, p. 168.) 
1897. Wilson, George : " On Some Differences that distinguish the Goldfields of the Hauraki 

Mining District." N.Z. Inst. Min. Eng., vol. ii, p. 17, 1897. 
1897. Campbell, Joseph : " Volcanic Zone of the Hauraki Goldfields." Scottish Geol. Mag., 

p. 246, 1897. 
1897. Wauchope, J. A. : " The Goldfields of the Hauraki District. " Trans. Fed. Inst. Min. 

Eng., vol. -xiv, pp. 19-45. 



6 

1897. McCombie, John : " Treatment of Ore on the Hauiaki Goldfield." Trans. N.Z. Inst. 

Min. Eng., 1897. (Copied N.Z. Mines Record, vol. i, p. 399.) 

1898. Don, J. R. : " The Genesis of Certain Auriferous Lodes." Trans. Amer. Inst. Min. 

Eng., vol. xxvii. 
1898. SchifE, F. : " Les Mines D'Or de la Nouvelle-Zelande." Pubhcation du Journal le 

Genie Civil, 6 Rue de la Chaussee-d'-Antin, 6 Paris, 1898. 
1898. McKay, A. : " Report on the Occurrences of Cinnabar in the Kaueranga ^'alley, Thames 

County." C.-9, p. 8, 1898. 
1898. McKay, A. : " Analyses of Cinnabar Ore from Kaueranga." N.Z. Mines Record, 

vol. iv, p. 390. 
1898. McKay, A. : " Geological Survey of Cape Colville Peninsula (Progress), 1897-8." C.-9, 

1898. 
1898. Allen, F. B. : " Minerals in the Gold-bearing Reefs of Thames." N.Z. Mines Record, 

vol. ii, p. 20. 
1898. Perham, T., and Wilson, George : " Reports on Water-conservation on Hauraki Gold- 
field." C.-4 and C.-4a, 1898. 
1898. " Plan of Pumps in Queen of Beauty Shaft." C.-3, p. 54, 1898. 

1898. " Sudden Influx of Gas : Kiiranui-Caledonian Mine, Thames." N.Z. Mines Record, 

vol. i, p. 376. 
1899j' Park, J., and Rutley, F. : " Notes ou the RhyoUtes of the Hauraki Goldfield, New Zea- 
land." Q.J.G.S., vol. Iv. p. U9. 

1899. Bromly, A. H. : " Treatment of Gold-ores in the Hauraki Peninsula." Eng. & Min. 

Journ., N. York. (Copied C.-3, 1899, p. 181.) 
1899. McKay, A. : " Report on the Pumice-stone Deposits of the Middle Part of the North 
Island." C.-9, p. 16, 1899. 

1899. Allen, F. B. : '" Molybdenum in Thames District." N.Z. Mines Record, vol. ii, p. 475. 

1900. Park, James : " Notes on the Geological Examinations of the Thames Goldfield." 

N.Z. Mines Record, vol. iii, p. 376. 
1900. Park, J., and Rutley, F. : " Additional Notes on some Eruptive Rocks from New Zea- 
land." Q.J.G.S., vol. h-i, 1900, p. 493. 

1900. Allen, F. B. : " The Borehole at the Thames." N.Z. Mines Record, vol. v, p. 506. 

1901. Allen, F. B. : " Tellurium in the Ores of the Hauraki Goldfield." N.Z. Mines Record, 

vol. iv, pp. 467-470. 
1901. Park, James : " Notes on some Andesites from the Thames Goldfield." Trans., xxxiv, 

p. 435. 
1901. • Park, James : " On the Secular Movements of the New Zealand Coast-Une." 

Trans., xxxiv, p. 440. 
1901. McKay, A. : " Report on the Correspondence of the Shoots of Gold East and West of 

the Moanataiari Shde, Thames." C.-IO, p. 34, 1901. 

1901. Haszard, H. D. M. : " The Drainage of thePiako Swamp, Thames." N.Z. Mines Record, 

vol. V, p. 366. 

1902. McKay, A. : " Deep-level Mining at the Thames." N.Z. Mines Record, vol. v, p. 501. 

1902. Park, James : " The Geology of Mines and Minerals." Otago Times and Witness 

Newspaper Company (Limited) (1902). (Cinnabar at Otanui, p. 20.) 

1903. Park. James : " On the Jiirassic Age of the Maitai Series." Trans., xxx\i, p. 431. 

1904. Paul. Matthew : " On the Occurrence of Large Bodies of Ferrous Sulphate in the Gold- 

mines of Thames Goldfield." Trans., xxxvii, p. 551. 
1904. " Boreholes at Thames." N.Z. Mines Record, vol. \Ti, pp. 76, 302, 397. 
1904. Morgan, P. G. : "Water in the Hauraki Goldfield, New Zealand." Eng. and Min. 

Journal, N. York, 15th September, 1901, p. 429. 



1905. McKay, A., and SoUas, W. J. : " Rocks of the Cape Colville Peiiinsiila." 1905-6, 
vols, i aud ii. 

1905. Park, James : " Thermal Activity in its Relation to the Genesis of certain Metal- 
liferous Veins." Trans., xxxviii, pp. 20-33. 

1905. Park, James : " Notes on the Influence of Country Rock in Relation to the Distribution 
of Valuable Contents of Lodes, with Special Reference to the Productive Zone of 
the Thames Goldfield, New Zealand." Trans., xxxviii, p. 601. 

1905. Lindgren, Waldemar : " The Hauraki Goldfield, New Zealand." Eng. & Min. Journ., 
N. York, 2nd February, 1905. (Copied N.Z. Mines Record, vol. viii, p. 370.) 

1905. Morgan, Percy G. : "The Hauraki Goldfields" (Waldemar Lindgren's paper). N.Z. 
Mines Record, vol. viii, p. 465. See also Eng. and Min. Journal, N. York, 4th May, 
1905, p. 861. 

1905. Marshall, P. : " The Geography of New Zealand." Publishers : Whitcombc and 

Tombs, Welhngton, N.Z. 

1906. Galvin, P. : " The Mining Handbook of New Zealand." (Preface by Hon. James 

McGowan.) 
1906. Park, James : '" Notes on the Formation of Zones of Secondary Enrichment in certain 

Metalliferous Lodes." Trans., xxxix, pp. 93-97. 
1906. Park, James : " Notes on the Distribution of Ores in Horizontal Zones in A'ertical 

Depth." Trans., xxxix, pp. 90-92. 
1906. Park, James : " A Text-book of Mining Geology." Publishers : McMillan and Co. . 

1906. Loughnan, R. A. : " The First Gold Discoveries in New Zealand." Government 

Printer, Wellington. (Reprint from N.Z. Mines Record, vols, ix and x.) 

1907. Adams, E. F. : " Maps of the Main Reefs on the Hanging-wall Side of the Moanataiari 

Slide. Thames Goldfield." C.-3, p. 8, 1907. 

1908. Maclaren, J. Malcolm : " Gold : Its Geological Occurrence and Geographical Distribu- 

tion." Publishers : The Mining Journal, London. 

1909. Bell, J. Mackintosh : " Economic Geology of New Zealand. Trans. Austr. Inst. Min. 

Eng., vol. xiii, 1909. 

1909. Park, James : " History of Mining in New Zealand." Min. .lourn. (London), 75th anni- 
versary number ; August, 1909. 

1909. Finlayson, A. M : " Proljlenis in the Geology of the Hauraki Goldfields, New Zealand." 
Economic Geology, vol. iv. No. 7, 1909. 



8 



CHAPTER II. 



HISTORY AND TECHNOLOGY OF MINING ON THE THAMES GOLDFIELD. 



History of Mining Development . . 8 Mining and Treatment of Ores . . 11 

Mineral Production . . . . 10 > Labour and Financial (Conditions . . 13 

History op Mining Development. 

Although gold-mining in Hauraki dates back to 1852, the year of the discovery of gold at 
Coromandel, it was not until 1865 that the presence of the metal was suspected at Thames, 
an equally accessible locality distant only twenty-five miles from the older centre. In the 
latter year fragments of highly auriferous quartz were discovered in Karaka Creek, but owing 
to the unfriendly attitude of the Natives further prospecting was temporarily abandoned. 
As the result of negotiations between the representatives of the General Government and the 
Natives, a block of land between Kuranui and Karaka creeks was, on the 30th July, 1867, 
thrown open for raining, and prospectors again entered the field. On the 10th August of 
the same year, Hunt, White, Clarkson, and Cobley discovered a rich gold-bearing vein in 
Kuranui Creek. This find caused considerable excitement, an immediate rush to the new 
El Dorado, and the staking of claims in every direction. 

The field was of such a character as to render it decidedly favourable for rapid develop- 
ment : gold was found in many of the outcropping veins ; the country rock was fairly easily 
penetrated, and required but little timbering ; furthermore, the metal was readily extracted 
at small expense from the rich bonanza ore. The field, therefore, at its earliest stages was 
almost as profitable as rich alluvial diggings to the more fortunate parties of miners who 
owned productive claims. 

So rapid was the progress of the industry that " at the end of December, 1868, or seven- 
teen months after the first proclamation of the field, not only had two other districts, Tapu 
and Puriri, been started, but about 1,200 claims had been taken up near Shortland (Thames), 
between 800 and 850 of which were then actually working, and probably 600 of the number 
had seen gold in greater or less quantities. Twenty-seven crushing-machines were on the 
ground and thirteen were going up. The yield of gold had exceeded 83,000 oz., valued at 
more than £200,000."* 

The history of Thames from these early times to the present day differs little from that 
of every other mining camp depending upon auriferous veins of the bonanza type. The 
historical data and statistics are, however, far from satisfactory, and scarcely admit of tracing 
in sequence the principal events connected with the field's development. Probably the 
diagram (p. 10), setting forth graphically the annual value of the gold-output, will also 
recall the dates of those periods of intense mining excitement which attended the discovery 
and extraction of the several wonderfully rich bonanza ore-shoots. 

The pioneer claim — the Shotover — is reported to have returned to Hunt and his three 
mates gold to the net value of £40,000 per man, while the shareholders in the company sub- 
sequently formed received £15,120 in dividends. 

* " Second Report on Thames Goldfield," F. W. Hutton, Rep. G.S., vol. v, 1869. 



9 

At a very early date most of the other promising claims passed, like the Shotover, into 
the hands of small minuig companies, and in many cases a consolidation of small holdings 
was effected. The following dividend-payments made by some of the more fortunate of the 
companies may be tabulated : — 

The Shotover Company paid in dividends £15,120. 

The Long Drivfe Company paid £82,000. 

The Kurauui Company paid £41,277. 

The All Nations Company paid £41,445. 

The Manukau Company paid £15,750. 

The Golden Crown Company (irrespective of the large amount divided by the original 
shareholders) paid £141,904. 

The CaledouiaTi Company paid £553,440 in the first year of its existence. 

The Cure Company paid £17,000. 

The Moanataiari Company paid £121,365. 

The Nonpareil Company paid £14,670. 

The New Alburnia Company (vide Mines Report, 1889. p. 37) paid £72,500. 

The Old Whau Company paid £11,650. 

The Queen of Beauty. Queen of the May, City of London, Piako and Bird in Hand, 
and Bright Smile claims together out-turned over £368,000 (1869-87), and 
paid large dividends, which are, however, not recorded. 

The Prince Imperial Company paid £60,750. 

The Cambria Company paid £80,475 (£48,825 was paid in one year — 1884-5 — or 
dividends amounting to £1 lis. per share on Is. 2d. paid up). 

The Saxon Company (1887-1893) paid £15,417. 

The Waiotahi Company has paid in dividends £391,800 (£40,200 was paid between 
1871 and November, 1901, and £354,610 between November, 1904, and the 
3l8t December, 1908). 
The output of Thames attained its ma.ximum in 1871. when the value of the gold entered 
for export amounted to £1,188,708. This was mainly the product of the Caledonian Com- 
pany's mine, in which was located the greatest bonanza of the field, and one of the richest 
recorded in the aimals of (juartz-mining. Following the subseijuent fluctuation of the gold- 
output (vide diagram, p. 10), it will be noticed that low-water mark was reached between the 
years 1897 and 1898. This seems remarkable, in that these particular years are among those 
generally spoken of as the " time of the boom," one of the greatest periods of mining excite- 
ment that the Auckland goldhelds have ever experienced. The initial causes of this extra- 
ordinary wave of mining activity, which affected Thames in conmiou with the other centres, 
may be ascribed to the returns from the phenomenally rich veins of the Hauraki Mine at Coro- 
mandel, and to the solid, steadily increasing gold-output from the Waihi and other mines in 
the southern portion of the Hauraki Division. The area pegged out was relatively enormous, 
and prospecting operations were consequently extended from the previously well-known 
centres to the back country. Colonial capital for mine-development was largely supplemented 
by English capital, and numerous companies were formed principally to exploit properties 
situated in the older-established centres. As is inevitable in all such periods of mining excite- 
ment, it cannot be affirmed that the expenditure of money was in all cases duly warranted, 
or that where expenditure was justified the mining operations were in every case intelli- 
gently directed. 

To the lavish expenditure of English money at this time, Thames owes its main pumping 
plant — the Thames-Hauraki — as well as several substantial stamp-batteries. In most cases 
the expenses of flotation, management, and surface equipment were so heavy that only a 
small balance of the working capital of the English companies was available for actual pro- 



10 

spectinp and development-work underground. The result was an early cessation of their 
mining operations, followed by the sale of properties and the liquidation of the companies. 

From 1899 to 1904 the field experienced the reaction which inevitably followed the 
" boom," and no discoveries of note are to be recorded. Before the end of the latter year, 
however, the Waiotahi Mine was destined to demonstrate in unmistakable manner that thp 
possibilities of a field of this character can never be gauged, and that it is hardly safe to regard 
as " worked out " even the upper levels of a particular mine, let alone those of the whole field. 
The Waiotahi Mine covers less than 23 acres, and prior to the discovery of this bonanza 
had been worked continuously for over thir-ty years at a steady profit, but as its pay-ores 
were considered just about exhausted the market value of the shares (6.000 at £3) had fallen 
to 8s. each. The new ore-shoot was discovered in certain workings on No. 4 level, and con- 
tinued downwards for some 130 ft., yielding gold to the value of £463,781* in four years. The 
company, from this bonanza, which proved to rank second only to the famous Caledonian, 
paid dividends amounting to £354,600, and the market valuation placed on the property 
found a maximum at about £720,000. 

Renewed impetus was given to mining at the Thames by these sensational developments 
in the Waiotahi, but the total gold-output attributable in recent years to the other claims 
has proved disappointing. 

The main hope of the field is now centred in exploiting the deeper levels of that particular 
belt of country at Thames which has in the past yielded the bulk of the gold-output. 

Mineral Production. 

The total gold-silver production of the Thames Subdivision cannot be accurately stated. 
owing to the lack of reliable statistics relating to the earlier years of the field, but the foUo^ving 
figures can be regarded as a fairly close approximation : — 

The value of the output from the Thames County from the opening of the goldfield in 
1867 to the 31st December, 1908, as compiled from figiu-es appearing in the " Thames 
Directory " of 1881, the " Handbook of New Zealand Mines " of 1887, and the official reports 
of the New Zealand Mines Department from 1887 to 1908, totals £7,075,131. 

The accompanpng diagTam sets forth graphically the estimated value of the yield of each 
particular year, together with the figures making up this gr-and total. 

Included in the Thames County, but hing outside the hmits of the Thames Subdivision 
of the present survey, are the mines of Tairua, Ohui, Upper Puriri, Omahu, Hikutaia, and 
Gumtovvn. The total recorded output of these mines dates from 1888, and has an approxi- 
mate value of £164,500. 

The net selUng-value of the total gold-silver production of the area under re\iew may 
therefore be stated approximately as £6,910,631. If to this amount be added the gold duty 
(a revenue tax), amounting to, say, £172,800, which has been deducted by the piu'chasing 
banks, it will bring the output figures of the subdivision up to £7,083,431. Ha\ing regard to 
the loss of old unofficial records, and also to the metal which may have been sold through 
channels other than the banks and not exported through the Customs, the figures are much 
more likeh* to be under than over the true mark. 

It is not certain how much of the above-stat«d value should be accredited to silver, which 
occurs throughout the mining field alloyed with the gold in the form of electrum : probably 
£85,000 represents the minimum value of the silver produced from the opening of the field 
to the 31st December, 1908. 

In addition to gold and silver, several parcels of picked complex sulphide ore containing 
lead, copper, and zinc, and also a few hundredweights of mercury-bearing ore (cinnabar), have 
been exported, but the total value of these metals is almost negHgible. 

* Included here with the gold yielded by the bonanza shoot is a relatively small amount derived from the 
Cure and other minor branch veins, which were being worked at the same time. 

















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11 

Mining and Treatment of Ores. 

The methods of mimng in vogue at Thames are not materially different from those 
employed in other fields where gold-quartz veins of similar character are worked. 

Vertical rectangular shafts give access to the various mines on or near the foreshore, 
and adits to the ground forming the hilly portions of the field. 

The rock of the Thames mines is usually hard enough to stand imsupported in cross- 
cuts, excepting in local areas of shattered or " swelUng " country and in the vicinity of faults 
and certain of the veins. A good deal of the interbeddcd flow and breccia country of Tararu 
and elsewhere can be termed heavy ground, and in places calls for frequent renewals of the 
sets in the working-levels. The mine-timber is usually kauri. This is split for use as sets 
and slabs in the underground roadways, and is sawn for shaft requirements. The shafts 
are timbered throughout, the larger ones with frame sets, the smaller ones either in the 
same manner or with box sets. 

In the drainage of the principal group of mines — those working below the ground-water 
level near the foreshore at Thames — the several proprietary compauies co-operate. Drainage 
is effected by means of a powerful double-acting Cornish pump (plungers and drawlifts 25 in. 
diameter), operated by steam-power. This pumping plant, and the Thames-Hauraki shaft 
in wliich it is installed, is the property of the Dominion Government, and is under lease to 
the Thames Drainage Board. 

The ventilation of the group of mines mentioned above depends in the niain on the natm-al 
movement of the air through the workings via downcast and upcast shafts, certain workuigs 
of adjoining mines being in communication. Air, conveyed in pipes from compressors, 
or again from small fans or water-blasts, is frequently required in certain offset drives and 
other workings. As mentioned in another section of this report, the abundance of mine- 
gas (a mixture of nitrogen and carbon-dioxide) emanating in places from the country rock 
renders satisfactory ventilation a difficult problem in this group of mines, and one that will 
require a great deal more attention when the deeper levels come to be exploited. The ventila- 
tion of the numerous mines working from adits is, of course, a more simple matter, and is 
effected by the usual methods employed elsewhere. 

Hoisting in the shafts is effected by steam. Cages are employed, and the mine cars or 
trucks, holding usually from 6 cwt. to 10cwt.,are raised to the surface. In winzes or small 
shafts hand-windlasses or air-winches are employed in hoisting the buckets. Oil-engines 
are in one or two cases used to furnish power for the same purpose. 

The ore is won by the usual procedure of driving and overhand stoping. In the stopcs 
a few stulls are usually the only timber required. Filling of the stopes is always practised. 
The waste rock and non-payable vein-quartz broken in the ordinary course of operations is 
more than sufficient for filling-material. 

In the case of the smaller veins the drive or stope is generally carried along the actual 
foot-wall, the vein being what is termed " stripped " ; the veinstone is then broken down 
from time to time. Where very rich ore is expected, sacking is placed beneath the sollar 
boards or plank floors to minimise the chance of valuable material being lost. The picked 
stone — or " specimen stone " — is sorted out from the general ore for safe keeping and special 
treatment. 

Air-drills are employed to some extent in three or four of the mines, but the hammer 
and hand-drill is everywhere part of the usual equipment for breaking ground. 

The metallurgical treatment which was in vogue at Thames when the greater part of 
the field's output was obtained was decidedly simple, but by no means efficient. It consisted 
of crushing the ore in batteries of comparatively slow-running Ught stamps, the ore, first 
reduced by spawUng, being hand-fed into the mortar-boxes. Inside- and plate-amalgama- 
tion was practised. The pulp from the plates was run over ripples and blanket strakes, 
affording a Hmited amount of concentrates, which were further ground and subjected to amal- 



12 

gamation in berdan-pans. In certain cases tailings arrested as the result of a rough concen- 
tration in straight buddies outside the mill were stacked and retmned for berdan-treatment. 
The total value of the gold in the taiUngs which, under this treatment, swept through the 
sluices from the various batteries at Thames, to be deposited on the foreshore or scattered 
by the waters of the firth, is relatively enormous. Professor James Park, formerlv Director 
of the Thames School of Mines, in 1893 conducted certain tests at the Cambria, Moanataiari, 
and Norfolk batteries, mills fairly representative of all those then on the field. These 
tests proved conclusively that the extraction obtained in treating the general ore of the field 
did not exceed 51-5 per cent, of the assay value.* 

The first attempt to improve the treatment was the introduction into some of the mills 
of modern grinding and amalgamating pans. This resulted in better extractions, and a great 
quantity of tailings which had been stacked and tailings which had reached the foreshore of 
the harbour were treated at a profit. That the losses Avere still heaAy. especiallv in the case 
of the more highly mineralised ores, was proven by further tests made at the School of Miues.f 
Pyritous quartz from the Waiotahi Mine assaj^ng £2 4s. 3d. per ton, yielded to careful treat- 
ment by the Washoe process — probably the best amalgamation treatment practicable — a 
return of only 66 per cent. 

The cyanide process, which was for a long time held to be inappUcable to Thames ores, 
came gradually into favour, and is now employed with success in the mills of the Waiotahi 
and the Day Dawn and Norfolk companies, and in the mill forming part of the Thames Fore- 
shore Dredging Company's plant. A cyanide plant also forms part of the Monowai Company's 
mill at Waiomo. Excepting in case of the ores containing an appreciable amount of chalco- 
pyrite and those of less frequent occurrence containing tellurides, the extractions by the 
cyanide process, given careful manipulation, are satisfactory. Even in the case of those more 
refractory ores, the cyanidation of the sands freed from concentrates is effective. 

Concentration processes have certainly not received the attention at Thames that their 
importance merits. For many of the ores in which the values are largely associated with 
complex sulphides, and also for those containing tellurides. cheap crushing and effecrive con- 
centration, followed by cyanidation of the sands and the special treatment of the concen- 
trates locally, or their shipment to smelters, appears imperative if the mines out-turning 
such ores are to be worked to the best advantage. These remarks apply to the Syhda, Watch- 
man, and Waitangi mines among others at Thames, and to several claims located in the same 
andesitic complex extending northward to and beyond Waiomo. 

Smelting has been attempted on more than one occasion at Thames. A modern smelter 
with a capacity of 250 tons burden has recently been erected by a company styled the Ferguson 
Mining and Smelting Company. The smelter-sit« is on the western shores of the peninsula, 
at the mouth of Waiomo Valley, a locaUty distant ten miles northward by coach-road from 
Thames. The company, unfortunately, was ill-ad%-ised from the outset : no intelHgeut con- 
sideration was given to the vital question of ore-supplies : nor did any reliable estimate appear 
to have been made as to the cost of the required fluxes and fuel, all of which had to be shipped 
to the site from widely separate points. A two-days demonstration of smelting — cost not 
considered — was carried out, and the works subsequently closed down. 

While it is certain that the Thames SubdiAision is capable of supplying an appreciable 
amount of smeltable concentrates from complex sulphide ores, the crude ore itself, which 
is highly siliceous, will never pay to smelt locally. The supply of ore suitable for smelting is 
small ; its average value is low, and, in addition, the cost of importing the necessarj' fluxes 
and fuel is prohibitive. 

In respect of motive power, the Thames mining centre owes much to its water-supply, 
which is derived from the Kauaeranga River. A volume averaging about 1,500 cubic feet 
per minute, with a head of 150 ft. at the penstock, is available. Most of the batteries are 



* C.-3, 1893, p. 5. t C.-3, 1895, p. 7. 



13 

worked by water-power. Steam, generated by coal, mostly railed from the Waikato collieries, 
is, however, used for pumping and winding operations. The actual cost of this steam-power 
is not ascertainable, but even at the main pumping-station, where operations are continuous, 
it is probably not less than £18 per horse-power per annum. This compares unfavourably 
with the cost of power generated by large producer-gas plants, but the applicability of 
such gas-power to permanent pumping operations is still a debatable question. 

Of the mining companies operating beyond the Umits of Thames Town, the Day Dawn 
and Norfolk derives water-power from the creek in the \ncinity of its mill. The Monowai 
Company, at Waiomo, used water-power supplemented by a small producer-gas plant. The 
Otonui Mining Syndicate are using a kerosene-engine in connection mth their limited pumping 
and winding operations. 

In conclusion, it should be stated in connection with mining and miUing practices that 
Thames is a comparatively old field, and the equipment of many of the mines must now be 
considered rather obsolete. The mine-manager of to-day may be handicapped in his work 
by the constructions of earlier days. For instance, he may have to hoist through a shaft 
of insufficient dimensions, thus limiting the size of every car or truck in his mine. Again, 
his mill may be badly situated, old-fashioned, and inefficient. The requirements to insure 
economical mining and milling are well recognised, but the want of confidence, generally 
born of experience, in the ability of a particular claim to afford pay-ore continuously for an 
extended period is the prime reason for the existing state of affairs. It is to be hoped that 
the general co-operation now contemplated in connection with deep-level exploitation may 
place both mining and milling on a better footing. 

Labour and Flnaxcial Conditions. 

The general conditions of labour on the Thames mining field arc, and always have been, 
fairly satisfactory, and consequently disputes, strikes, or lock-outs of any moment have never 
occurred. 

The minimum rate of wage is at the present time fixed by an arbitration award. 
Ordinary miners receive 8s. 6d. per day of eight hours ; machinemen, 9s. ; shaft hands (six- 
hour shifts), 9s.; engine-drivers, lOs. ; mine-foremen or underground bosses, ]()s. to lis.; 
battery hands, an average of 8s. 6d. ; battery-foremen, lOs. and upwards. 

The mining country' is all Crown land or Native land open for mining, and held under lease 
by various companies, syndicates, and private individuals. Many of the small holdings of the 
early days of the field have been consolidated, and are now held by a comparatively few com- 
panies. The registered companies listed by the Stock Exchange as working, or holding under 
protection, mining claims within the subdivision number twenty-four. 

The number of men employed, which varies considerably owing to the alternate periods 
of mining activity and depression, is at present between two and three hundred. 

The tribute or leasing system is quite a feature of Thames mining. The tributes are 
usually granted for periods of from six to twelve months. The royalties deducted by the 
companies usually amount to 10 per cent, of the total gold won over and above what will 
afford the tributers a return amounting to half the current rate of wages. Tributes in a mine 
are usually taken by persons who have formerly worked as wages-men for the proprietary 
company. The advantages and disadvantages of the system from the company's point of 
view are certainly open to argument ; but, granted careful supervision on the part of the 
company's officers, the results are, on the whole, satisfactory. 

Gold exported from Thames, in common with the whole North Island of New Zealand, 
bears an export duty. The purchasing banks on this account deduct from the sellers an 
amount equal to 2s. per ounce, based on a fineness of 0-992(). The revenue accruing from 
this gold duty reverts to the Thames Borough Council or to the Thames County Council, the 



14 

local body having jurisdiction over the area from which the gold is derived. The raining 
properties at Thames, on account of this special tax, are not assessed for local rating purposes. 

The nominal capital of the Thames mining companies varies from £5,000 to £100,000, 
divided into from 60,000 to 300,000 shares of a par value of from Is. to 20s. Needless to say, 
the nominal capitalisation of a company is no criterion as to the value of its property. The 
value of a mine is estimated by the market price of its shares, but in few mining fields is the 
appraisal of mining properties more difficult than at Thames. Most of the companies are 
in reality prospecting rather than mining companies, and even a company that has the good 
fortune to strike a bonanza which may in a year or two repay its capital many times over 
usually falls back again very soon into the prospecting stage. 

The working capital of nearly all these mining companies has been subscribed in Auck- 
land, and in the province of which it is the chief commercial centre ; but during recent years 
capital is being drawn to some extent from Welhngton and further southward. EngUsh 
companies acquired certain properties at Thames during the last period of considerable mining 
excitement (1895-1900), but these have been notably unfortunate, and, with the exception of 
the Kuranui-Caledonian Company and the Day Dawai and Norfolk Gold-mining Company, have 
withdrawn from the field. The well-equipped Thames-Hauraki pumping plant, now the pro- 
perty of the Dominion Government, which contributed a substantial subsidy towards its 
erection, and a few comparatively large stamper-batteries, some of which never dropped a 
stamp for the companies that installed them, mark the failure of certain of these unfortunate 
ventures. 

Figures relating to the actual costs of mining and milling at Thames are not available. 
Owing to the nature of the ore-occurrences, the mining and subsequent milling of ore is often 
rather intermittent. If to the expense actually incurred upon ore raised the cost of mine- 
development and prospecting-work is added, the total cost on the tonnage is necessarily very 
high. 

The estimation of ore-reserves may in certain cases be roughly approximated, but, as 
a rule, this resolves itself into mere guesswork, and is not attempted. Even in ore developed 
— blocked on four sides — there is little guarantee that it will crush anything approaching 
an estimate. It may do so ; on the other hand, it may fall far short of this estimate, or, 
again, greatly exceed it. 

The practice of ore sampling and assaying is important in those claims in which the values 
are associated with complex sulphides and occasionally with tellurides. In case of those 
operating on the less refractory ore — vein-quartz with more or less pyrite — the milHng of 
parcels of a few tons from different points has been found the most satisfactory test. The 
mill-tailings from such parcels should, however, in all cases be sampled and assayed. 

With a view to reducing mining-costs, there can be no doubt that a further consohda- 
tion of claims at Thames would be advisable. In the case of a small company, with a few 
men employed underground, the cost of management at the mine added to that at the regis- 
tered office bears an undue proportion to the actual expenditure underground. Consolida- 
tion would not only rectify this, but would insure more up-to-date practices in mining and 
milling, and allow of more remunerative salaries being paid to a less number of highly 
qualified mine-managers. Against this recommendation it may be argued that the existence 
of a number of small companies co-operating to a certain extent in respect to drainage, 
ventilation, and in the driving of the main crosscuts is favoured by a large section of the 
speculating public who contribute the bulk of the working capital ; thus consohdation might 
be attended with an actual curtailment of mining operations. 



15 



CHAPTER III. 



OUTLINE OF THE GEOLOGY AND PHYSIOGRAPHY OF THE AREA. 



Page Page 

Geology . . . . . . . . 15 Physiography . . . . . . 16 

Geology. 

The oldest rocks existing in the Thames Subdivision are folded sedimentaries, referable to 
the Tokatca Hill Series.* They are non-fossiliferous, and consist of argillites and grauwackes 
with interstratified bands of much-altered acidic tuffs, locally termed " felsitic mudstones." 

The Manaia Hill Series,! of Jurassic age, are next in the sequence, and unconformably 
overUe the older terrains. They consist of fine conglomerates, grits, grauwackes, and argil- 
hies derived from the denudation of a land-surface consisting largely of volcanic rocks, both 
of andesitic and rhyoHtic character. 

Subsequent to the deposition of the Manaia Hill Series there ensued the great erogenic 
movements which have determined one of the most pronounced breaks in the whole New 
Zealand geological sequence. Folding and elevation of the strata in the subdivision resulted, 
the flexures produced causing the beds to incline at various angles, and in places to assume 
positions even of verticaUty. A long period of subaerial erosion and denudation followed, with 
the attendant dcxelopment of a submature topography. This old land was affected by the 
gradual — in part intermittent — submergence which in Early Tertiary times was general 
throughout New Zealand, when the principal coal-bearing strata were deposited. Within the 
Hauraki area remnants of these beds — the Torehine Series — are preserved in the northern 
portion of the peninsula. If such beds ever existed within the limits of the Thames Sub- 
division, as is quite probable, they have either been completely removed by agencies of denuda- 
tion or they lie concealed beneath the volcanic rocks. 

The great earth-movements to which the Torehine Series owes its uplift involved folding 
and tilting with — at least, in the northern part of the peninsula — very irregular elevation 
of these and older rocks. 

Following, or in part contemporaneous with, these great earth-movements the stupendous 
volcanic energy, which, with certain periods of intermission, characterized the whole of the 
subsequent Tertiary era, first manifested itself. Great piles of tuffs, breccias, and lavas of 
andesitic character were extruded from numerous volcanic vents and fissures in the corrugated 
sedimentaries. The " Tertiary Volcanic Rocks of the ' First Period ' " is the gioup-name 
apphed to this great accumulation of extruded andesitic material, which in places even now 
exceeds 2,5()0 ft. in thickness. The tuffs and breccias are well consolidated, and, together 
with the lavas, have all been considerably altered by hydrothermal action. 

A period of quiescence followed the last outbursts of these Early Tertiary eruptions, and 
the irregular land-forms which were largely the result of original volcanic accumulation were 
considerably modified by agencies of subaerial erosion. 

* Tokatea Hill Series, of Bulletin No. 4 (New Series), Coromandel Subdivision, 
f Manaia Hill Series, of Bulletin No. 4 (New Series), Coromandel Subdivision. 



16 

Following this the Tertiary volcanic rocks of the " Second Period," known as the 
" Beeson's Island Series," were extruded. These consist of heavy accumulations of ande- 
sitic and dacitic tuffs, breccias, agglomerates, and lava flows, the fragmental material being 
usually poorly consolidated compared with that of the older series. Thin coaly partings 
in places mark the unconformity between the volcanics of this group and more ancient rocks, 
or, again, mark minor pauses between successive eruptions of the later period. 

Tertiary volcanic rocks of the " Third Period " — the most recent extrusives of the volcanic 
complex — are rhyolitic tuffs and lavas, probably of Pliocene age. In the Thames area they 
cap most of the higher country to the east and south, and are in continuity with a widespread 
development of the same rocks in the Tairua-Waihi Subdivision immediately to the east- 
ward. 

Intrusive rocks undoubtedly occur in association with the volcanics here grouped under 
different headings, but, on account of a general similarity in the mineralogical character 
between the intrusive and the intruded rocks, they are often difficult to differentiate. In 
certain areas where the basement sedimentaries — especially those of Tokatea Hill Series — 
are exposed ramifying dyke rocks are conspicuous. 

The intrusive rocks of the subdivision are almost exclusively semi-basic in character, 
and are doubtless, in the main, the analogues of the Tertiary volcanics. The great dyke of 
glassy hypersthene-andesite, which breaks through the Phocene rhyolites and forms the Table 
Mountain, is a very conspicuous feature of the landscape of the area. 

The great deposits of siliceous sinter and chalcedonic quartz which characterize certain 
localities, the deep-seated alteration of various belts of the volcanics, the veins and ore- 
deposits wliich these altered rocks frequently enclose, are all evidences of former periods of 
intense hydrothermal action. Such phenomena doubtless represented the "^eruptive after- 
actions " which frequently mark the dying stages of vulcanism. 

Numerous faults of greater or less magnitude have affected the rock-masses of the sub- 
division, but only where they give topographic expression to the land-surface, or are revealed 
by imdergroimd mining, is their presence evident. The best known is the Moanataiari fault, 
which demarcates the upland and central blocks of the Thames mining centre. It is more 
than probable that the Firth of Thames, together with its naturally reclaimed portion — the 
lower Thames-Piako valley — is a graben or downfaulted area partially filled up by river- 
alluvium and estuarine deposits. The Moanataiari and, in all probability, the Beach "slide" 
are, at Thames, step faults connected with this great downthrow. 

A very general earth-movement, involving the tilting of the whole Hauraki land-mass 
on a north-east axial line, with attendant elevation in the north and west and subsidence 
in the south and east, has continued down to Late Pliocene, or perhaps even Pleistocene 
times. This is deduced from the very general south-easterly dip of the rhyolitic rocks and 
of the underlying Beeson's Island andesites, also from the existence of the many sunken-river 
mouths on the eastern and south-eastern coast-line of the peninsula. 

About the close of the Pliocene period all volcanic activity ceased in this region, and 
the main constructive geological work since that time has been the filling-in of the bays and 
inlets by fluviatile agencies — a work which is still in progress. Raised beaches and high- 
level river-terraces on the western side of the peninsula are due to the tilting earth-movement 
already mentioned, or to more recent negative movements of the strand-line. 

Physiography. 

The country included within the limits of the Thames Subdivision viewed rn masse falls 

naturally into two markedly different physiographic areas : («) That forming part of the 

comparatively elevated and deeply dissected land-mass of the Hauraki Peninsula and its 

further southern extension ; (b) that forming the low-lying Hauraki Plains (Thames-Piako 




x 



17 

Plain) bordering on the Firth of Thames, and skirting the western margin of the southern 
extension of the uplands. 

The trend of this portion of the Hauraki Peninsula is nearly north-south, and its width, 
which is fairly constant, measures about twenty miles. Only its western half, however, and 
a narrow strip of the high country bordering the Hauraki Plains further southward, lies within 
the limits of the area under review. 

Viewing the upland area from any position of vantage, preferably one of the major eleva- 
tions in the interior, it is apparent that the dominating physiographic feature is the main 
divide, a range of low mountains averaging from 1,700 ft. to 1,800 ft. in height, exhibiting a 
sinuous trend, in the main conformable to the longitudinal extension of the peninsular mass. 
From the main divide strike numerous spurs marking off tlie valleys of the various streams, 
while in places minor independent ridges and groups of -hills lie between the main range, with 
its deeply incised flanks, and the sea-border. The lowlands are inconspicuous ; they are con- 
fined to flats alonij the sea-margin, forming incipient coastal belts, and to the narrow flood- 
plains of the various streams. 

The main divide, known as the Cape Colville Range, continuing southward from the 
Coromandel .Subdivision, preserves a general trend of south-east for a distance of twelve miles 
to the source of the northern headwaters of Te Puru Stream, its average distance from the 
coast-line of the Firth of Thames being about five miles. The most conspicuous heights of 
this stretch are : Trigonometrical .Station No. 1,1(K), 2,263 ft. ; Papakai, 2,497 ft. ; and Mau- 
maupaki (Camel's Back), 2,688 ft. ; while the lowest saddles have elevations varjnng from 
1,200 ft. to l,4(X)h. From this source of Te Puru Stream the main range is continued as 
a bold spur striking south-west, and lying between the middle and lower portions of the 
Kauaeranga Valley and the Firth of Thames. The main water-parting, followed from the 
source of Te Puru, turns almost at right angles, and, striking eastward a distance of some 
six miles, crosses the Table Mountain, and passes beyond the boundary of the subdivision 
to the source of the Kauaeranga River. 

The new line of water-parting from the source of the Kauaeranga strikes a little west of 
south, marking off the drainage-areas of the Kauaeranga, Kirikiri, Puriri, and certain minor 
streams flowing to the western coast-line from that of the Tairua River, flowing to the eastern 
coast-line. Nowhere, however, does the actual crest of this portion of the main range lie 
within the Thames Suijdivision. This stretch of the mountain divide is a more recent geo- 
logical feature than that extending from Moehau to Thames, and consists mainly of the dis- 
sected and partially dissected plateau of Pliocene rhyolites. 

The Table Mountain owes its existence to a large dyke of andesite intruded into this 
plateau of easily eroded rhvolitic tuffs, and to the subsequent removal by denudation of 
these tuffs from the walls of the dyke. It is a flat-topped, steep-sided mountain about 
three-quarters of a square mile in area, with an approximate elevation of 2,800 ft. This 
mountain is separated by a saddle from the fairly flat-topped Table Moimtain Range, formed 
of the same dyke rock and portions of the rhyolites into which it was irrupted. 

The ridges and groups of hills more or less independent of the main range are principally 
confined to a rhyolitic area south and west of Whitianga Harbour. On the opposite side 
of the peninsula, however, a subsidiary ridge of stratified rocks between Waikawau and Kirita 
Bay trends parallel to the main range. 

The lowland area of the Hauraki (Thames-Piako) Plains rises very gradually from the 
margin of the spacious mud-flat of the Firth of Thames to 15 ft. or 20 ft. in the vicinity of 
Paeroa, some sixteen miles inland. Along its eastern border the general elevation is greater, 
owing to the coalescence of the fan deposits of the various streams draining the hilly coimtry 
with the alluvium transported from the upper valley of the Thames. 

The western coast-line of the peninsula from the south headland of Kirita Bay to Thames 
^—Thames, 



18 

is fairly straight, and devoid of indentations of any note. This is in marked contrast to the 
irregular, deeply indented coast-line of the Coromandel area immediately to the northward. 
The absence on the Thames coast-Hne of the irregularly disposed volcanic accumulations of the 
Beeson's Island Series, together with the coast-hne's more sheltered position, in part accounts 
for this variance. Further, if as already postulated the Firth of Thames is a partially filled- 
in and submerged graben or downfaulted block, such a relatively straight shore-line, and 
one devoid as it is of outlying islets, would be expected. The normal development of the 
valleys of the streams entering on this shore — among others, the Tararu, the Puru, and the 
Waiomo streams — however, would suggest that the faults northward of Tararu which bound 
such a graben He further seaward than the present coast-Une. 

A feature of physiographic interest is found in the fact that high-level river-terraces are 
common on the western side of the peninsula, but are absent on the eastern side. 

Raised beaches between Tararu and Waiomo are in places conspicuous, and mark a minor 
negative movement of the strand-line in recent times. It is of interest here to note that 
similar shingle beaches raised about 10 ft. above high-water mark occur at the Miranda, on 
the western side of the Firth of Thames. 

Stream-development throughout the Thames area is in general normal, and such as might 
be expected in a region of considerable reUef free from complicating features of glaciation, &c., 
and consisting mainly of irregularly bedded Tertiary volcanics in various stages of consoUda- 
tion and alteration. The abnormal drainage exhibited by several small streams at Thames 
as the result of the downthrow of the Moanataiari fault will receive notice in another section 
of this report. 

The Thames and Piako rivers, flowing with their broad meanders across the low-lying 
Hauraki Plains, and entering the upper reach of the Firth of Thames, drain a relatively large 
area of country, lying mostly, however, to the southward of the subdivision. The Thames 
River, which is much the larger, is navigable for coastal steamers as far as Paeroa, and gives 
access to the several sawmilUng and agricultural settlements situated between that centre 
and the sea-border. The Piako River drains a fertile but mostly undeveloped area, in which 
extensive draining operations are at present in progress. 

The Waiwawa, flowing into Whitianga Harbour, and the Kauaeranga, flowing into the 
Firth of Thames, are by far the largest streams draining the upland area. They have their 
sources in the east-west, striking Table Momitain Range of the interior of the peninsula, 
and, since their general courses are diagonal to the trend of the peninsula, they have relatively 
large drainage-areas. Of the other streams, the principal are the Waikawau, Mata, Tapu, 
Waiomo, Puru, and Tararu, entering directly the Firth of Thames ; the Kirikiri, Matatoki, 
Puriri, and Omahu, flowing into the River Thames, and the Kaimarama and Ounaroa, entering 
Whitianga Harbour. 



19 



CHAPTER IV. 



GENERAL GEOLOGY. 





Page ; 


Table of Formations 


19 




Pre-Jurassic and Jurassic Stratified Rocks . . 


20 




(1.) The Tokatca Hill Series 


20 


(2.) The Manaia Hill Series 


21 


Igneous Rocks . . 


22 


(1.) Tertiary Volcanic Rocks of the " First 






Periotl " 


22 




General Statement 


22 




Age .. 


23 




Distribution 


23 




Petrology 


23 


(2.) Tertiary Volcanic Rocks of the " Second 




Period " (Beeson's Island Series) . . 


25 


General Statement 


25 


Age .. 


25 


Distribution 


25 


Structure and Petrology . . 


25 


(3.) Tertiary Volcanic Rocks of the " Third 




Period " 


26 





Page 
Igneous Rocks — continued. 

(3.) Tertiary Volcanic Rocks, &c. — continued. 

General Statement . . . . 26 

Age . . . . . . . . 26 

Distribution . . . . 26 

Structure and Petrology . . . . 27 

(4.) Intrusive Rocks of Various Periods .. 27 
General Statement . . . . 27 

Age .. .. .. ..28 

Distribution and Petrology . . 28 

Loosely Consolidated and Unconsolidated 

Debris . . . . . . . . 29 

(n.) Late Pliocene or Pleistocene Deix)sits 29 
{!).) Recent Deposits .. .. ..29 

Regional Karth-movements and Faulting . . 30 
The Moanataiari Fault . . . . . . • 30 

The Collarbone Fault . . . . . . 31 

The Beach " Slide " or Fault . . . . 31 

Minor Faults . . . . . . . . 32 



Table of For.mations. 

The geological formations represented in the subdivision are tabulated in order of age as 
follows* : — 

Pre-Jurassic, — 

Tokatea Hill Series — 

Argillites and grauwackes, with interstratified beds of igneous material. 
Juiassic, — 

Manaia Hill Series — 

Argillites, grauwackes, grits, and fine conglomerates. 
Upper Eocene (?), — 

Tertiary volcanic rocks of the " First Period " — 

Andesitic and dacitic tuffs, breccias, agglomeiates, and lava-flows. 
Miocene, — 

Tertiary volcanic rocks of the " Second Period " — 

Andesitic and dacitic tufFs, breccias, agglomerates, and lava-flows. 
Phocene, — 

Tertiary volcanic rocks of the " Third Period " — 

Rhyohtic tufis, breccias, agglomeiates, and lava-flows. 
Intrusive igneous rocks of various periods — 

Diorite, porphyrite, andesite, and dacite. 
Pleistocene and Recent, — 

Unconsohdated and poorly consolidated debris — 

River-terraces, river-flats, drifting sands, talus slopes, sea-beaches, harbour 
muds, and swamp deposits. 



* Appendix shows the table of formations of this bulletin, together with the classifications of the rocks 
of the Hauraki Peninsula, by previous investigators. 

2' — Thames. 



20 

Pre-Jurassic and Jurassic Stratified Rocks 

Foldtxl strata of pro- Jurassic aiul Jurassic age form the basomoiit rocks of tlio Thames 
Subdivision, in common with the whole Hauraki Peninsula. In the Thames area, however, 
they have, compared with the Coromandel area farther northward, but Umited development 
at the existing sin-face. In the Tairua-Waihi Subdivision, to the east and south, they do 
not appear at all, nor have they been encountered in the deepest mine-workings (700 ft. below 
sea-level). 

Thi) pre-Jurassic and Jurassic rocks of Thames are respectively the Tokatea Hill Series 
and the Manaia Hill Series of the Coromandel Subdivision, described in Bulletin No. 4 (New 
Series), and the same nomenclature is here employed. As the petrology of these rocks has been 
fully described in the bulletin mentioned, little reference need be made to it in this report. 

(1.) The Tokatea Hill Scries. — The rocks of the Tokatea Hill Series consist of thin-bedded 
dark-coloured argillites.grauwackes, and interstratified beds of lighter-coloured igneous material 
— altered rhyolites and rhyohtic tufT or ash, locally termed " felsite." In addition, rocks exist 
which show lithological gradations between the ordinary sedimentaries — argillites and grau- 
wackes — and the interbedded rhyohtic tuils. These strata are intruded to a much greater 
extent than the overlying Jiu'assic sediments by dykes of andesite and porph\Tite. Though 
highly folded, the Tokatea Hill Series shows no signs of dynamic metamorphism, and even 
in the actual vicinity of the dykes the strata are but slightly affected by contact metamorphism. 
The interbedded rhyohtic tuffs, however, are altered and pyritised by the hydrothermal 
agencies which have effected the propylitisation of considerable masses of the overling 
andesites. The strata of this series have so far afforded no fossils, and their age is therefore 
unknown. In the classifications of previous geologists* they have been referred either to 
the Devonian, the Carboniferous, or the Triassic period. 

Within the Thames Subdivision these rocks are exposed at three localities — namely, 
the upper portion of the valley of Manaia Stream, the lower portion of the valley of Tapu 
Stream, and Rocky Point near Thames. Strata of this series have furthermore been pene- 
trated at and below a depth of 1,170 ft. from the surface in the Kuranui-Caledonian bore- 
hole, located near the entrance of the Moanataiari turmel, at Thames. 

Within the densely forested Manaia Valley the outcrops of pre-Jm-assic rocks appear 
for two and a half miles from north to south by possibly a mile in the opposite direction, and 
are continuous with a smaller area mapped in the Coromandel Subdivision. Where their dis- 
position is evident, the strata have a prevailing dip to the south-west at angles of from 60° 
to 70°. All the rocks typical of the series have development here — namely, the dark-coloured 
argilhtes and grauwackes, the light-grey pecuharly spotted rhyohtic tuffs and mudstones 
(" felsites ") invariably altered and pyritised, also the interbedded altered and silicified rhyo- 
htes or quart z-sericite rocks. Dykes of andesite and porphyrite intersecting the various 
rocks mentioned are conspicuous. 

In the lower gorge of Tapu Stream, distant not more than half a mile from the coast-hne, 
rocks of the Tokatea Hill Series occur. The exposure here reaches up the northern slopes 
of the valley, but measures in all less than 200 acres. The beds as seen in the gorge dip at 
high angles, first to the south-west and then to the north-east, as the stream-bed is followed 
upwards, thus forming an antichne. In addition to the predominating argilhtes and grau- 
wackes, tufaceous rhyohtic mudstones are present as hard compact bluish-gi'ey rocks, traversed 
bv numerous thin veins containing a good deal of pjrrite.t 

The hmited outcrops of the Tokatea Hill Series at Rocky Point, owing to their proximity 
to the mining centre of Thames, have been described in many former reports. Argilhtes and 

* See Appendix. 

f This rock is the same as that described in " Roiks of Cape Colville Peninsula," vol. i, p. 179^ 
and designated a " fine-grained siliceous grit." 



21 

giaiiwackes, dipping south-westward, at angles of about 35°, cover a small patch, on the beach 
below the liigh-tide mark, and are again met with up Waihoanga Creek about 20 chains from 
the shore-line. The interstratified acidic tuffs and mudstones — " felsites " — are exposed 
on the beach and in the road-cuttings for about 15 chains. These rocks are altered and 
pj-ritised, and in places bear a striking resemblance to much of the auriferous country of the 
Royal Oak Mine at Coromandel. A chemical analysis* of the altered felsitic rock is as 
follows : — 



Silica (SiOj) 
Alumina (AljO,) 
Ferric oxide (FejOg) 
Manganous oxide (MnO) 
Lime (CaO) 
Magnesia (MgO) 
Potash (KoO) 
Soda (Na^O) 
Titanium-oxide (TiO^) 
Iron-pp'ites (FoSg) . . 
Water and organic matter 



65-25 
20-32 
1-73 
0-05 
Nil. 
1-20 
3-90 
1-06 
0-50 
2-21 
3-78 



Total .. .. .. .. .. .. 100-00 

In the Kuranui-Caledonian borehole very hard black argillites and felsitic mudstones 
were encountered at a depth of about 1,170 ft. below sea-level. The induration or hardening 
is duo to numerous aiidesitic dykes which here intersect the strata. These strata, it may be 
inferred, persist further southward, underlying the andesitic rocks of the Thames mining 
centre, excepting, however, at particular localities where the andesites may be intrusive, 
or filling old craters. 

Regarding the general structure of the Tokatea Hill Series, it may be said that the strike 
of the rocks, or the main axis of the folding, is nearly conformable with the trend of the Hauraki 
Peninsula, and, taking a broader view, with the more northerly of the two main lines of 
folding which are evident in the North Island of New Zealand. 

(2.) The Mnnnia Hill Series. — The rocks of the Manaia Hill Series consist of fine con- 
glomerates, grits, grauwackes, and argillites, and present a niiirkwl uniformity in mineralogical 
composition wherever encoiuiterod in the Thames Subdivision or elsewhere in Hauraki. 

Fossils described by Professor A. P. W. Thomas as Inoceramus haasti and Belemnites sp. 
were found in these rocks at Manaia Hill, Coromandel Subdivision.! Further fragments of 
a belemnite, similar to the species described, have been collected from two oi three localities 
on the coast-line between Kirita Bay and Waikawau. Tho beds, on the available evidence, 
are regarded as belonging to the Upper Jurassic period. It is certain that uiuonformity 
exists between this series and the Tokatea Hill Series, although actual contacts i)i the Thames 
Subdivision were not obseiA'ed. 

The rocks of the Manaia Hill Series, particularly the conglomerates and grits, are cha- 
racterized by the abundance of igneous material which is mixed with the ordinary detritus. 
The erosion of flow andesites and flow rhyolites has contributed largely to these Jurassic 
sediments, but no vestige of these ancient widespread surface-flows is now apparent. The 
argillites and grauwackes occur as alternating thin-bedded strata, but the indurated fine-giained 
conglomerate, everywhere interbedded as heavier bands, shows in itself no very definite 
stratification. 



♦ Compare with analyses, p. 44, Bulletin No. 4 (Coromandel). 
•^ See Bulletin No. 4 (New Series), pj . 48-50. 



22 

The main exposure of this series measures about 16 squaie miles, and extends continuously 
along the coast-line from a point just south of Kirita Bay to half-way between the mouths 
of Te Mata and Tapu streams. The eastern portion of this exposure falls within the water- 
sheds of the Manaia and Whakarewa* streams. Up the main Waikawau Valley it extends 
back one and a half miles, and up the Mata Valley one mile from the coast-line. The beds 
throughout the whole of this area show a persistent dip to the south-westward, at angles 
varying from 30° to 75°. The exposure appears to represent the western limb of a major 
antichnal fold, conforming in strike with the trend of the peninsula. 

A very small exposure of fine conglomerates and grits of the series occurs at the road- 
quarry just south of Rocky Point. The rocks here are quite characteristic, but owing to 
alteration by hydrothernial waters they have hitherto been mistaken for audesite breccias 
with slaty inclusions. Near the head of Waihoanga Creek, about 30 chains back from Rocky 
Point, a small outcrop of these same conglomerates is to be seen. 

The locahties at which fossils — Belemnites sp. — have been collected are all on the actual 
coast-line, and may be acciuately recorded — (1) at points distant 2313 chains and 38-83 chains 
by road traverse north of the bridge crossing Otakeo Creek ; (2) at a point distant 69 chains 
northward by road traverse from the bridge crossing Waikawau Creek. In all cases the frag- 
mentary belemnite guards were obtained from pebble-conglomerates. 



Igneous Rocks. 

The igneous rocks here described comprise — (a) a great pile of massive and pyroclastic 
volcanics, which were at different periods in the Tertiary era extruded upon an irregular 
denuded surface of older stratified rocks ; (b) intrusives which form dykes and sills in the 
basement sedimentaries, or which intersect the Tertiary volcanics. 

Certain igneous rocks interbedded with the strata of the Tokatea Hill Series have already 
been briefly described, and need not be considered in this section. 

The Tertiary volcanic rocks range in chemical character from semi-basic to acidic, and 
are the products of three main periods of eruptive activity. The intrusive rocks do not admit 
of definite separation according to age, and have therefore been grouped. The igneous rocks 
are accordingly subdivided : — 

(1.) Tertiary volcanic rocks of the " First Period." 

(2.) Tertiary volcanic rocks of the " Second Period " (Beeson's Island Series). 

(3.) Tertiary volcanic rocks of the " Third Period." 

(4.) Intrusive rocks of various periods. 

(1.) Tertiary Volcanic Rocks of the First Period. 

General Statement. — The Tertiary volcanic rocks of the " First Period " cover an area of 
about 63 square miles in the Thames Subdi\asion, and are essentially of prime importance 
in that they constitute the main " auriferous series." They are entirely semi-basic or inter- 
mediate in character. The acidic rocks associated with this group in the neighbouring Coro- 
mandel Subdi\'ision are here not represented. 

These semi-basic rocks consist of andesitic and dacitic tuffs, breccias, agglomerates, 
and lavas, and are found comparatively fresh and in all stages of alteration and decomposition. 
The petrological examination of numerous rock-sections indicates that there exist only a few 
general lithological types, and that these tvpes are closely related to each other. Practically 
none of the lavas show vesicular structuie.f 



* Whakarewa Stream — the main tributary of the Waikawau. 

f A fairly large boulder of a vesicular basaltic andesite was found in the debris of Settler's Creek, Wai- 
wawa. 



23 

Any definite order of succession is seldom recognisable among the different members of 
this great volcanic formation, and, c\s'ing to the absence of well-marked types and to the 
persistence of propyUtic alteration and surface -decomposition, it is difficult to establish 
the identity of a particular flow rock or of a breccia-bed even in two neighbouring areas. 

These volcanic rocks are piled up in almost mountainous masses, and in the southern 
portion of the area persist to depths ceitainly 1,600 ft., and probably exceeding 2,000 ft., below 
sea-level. The usual land-forms characteristic of crateral vents have been obliterated, owing 
to extensive modification by agencies of subaerial erosion. 

Age. — The age of this volcanic formation has in the report on the Coromandel Subdivi- 
sion been assumed to range from Upper Eocene to Lower Miocene, and no further evidence 
bearing on this question has been afforded, by the area under review. 

Distribution. — The main belt of the " First Period " volcanics is continuous from the 
Manaia and Kaimarama watersh(Mis on the northern boundary of the subdivision to the Town 
of Thames, some eighteen miles farther southward. As the maps will indicate, this belt is of 
rather irregular shape. In the northern part of the subdivision it extends to both sides of the 
main range, but south of Te Mata Valley it appears to be confined to the western watershed. 
A relatively small patch (an inlier) of the same series is exposed in the valley of the Puriri, 
and extends southward into the watershed of the Omahu. 

Petrology. — In appearance the unaltered andesites and dacites of this group are usually 
dense, finely porph\Titic, black or greyish-black rocks, exhibiting small scattered glistening 
phenocrj'sts of plagiodase-feldspar and ferro-magnesian minerals. 

The associated tuffs, breccias, and agglomerates are well corLSolidatcxl, but are invariably 
considerably altered. The fragmentary material, irrespective of sparse inclusions of sedi- 
mentary rocks in the basal beds, is identical in mineralogical character with the rocks occur- 
ring as lava-flows or intrusives. A breccia containing angular inclusions varj'ing from 2 in. 
to 5 in. in dimension, set in a finer-grained matrix, is probably the most abundant type. 

Propyhtic alteration is widespread in connection with the rocks of this series, and various 
transition-stages between the fresher rocks and the propyhtes are recognisable. Advanced pro- 
pylitisation has resulted in both lavas and fragmentals being reduced to a somewhat similar 
product — a white, light-grey, purphsh-grey or greenish, only moderately hard rock — in which 
Uttle more than chalky-looking altered feldspars and secondary pyrite can be readily identified. 
The andesites and dacites, more especially in their altered condition, are very prone to 
surface-weathering, and are fre(juently covered to a considerable depth with the creeping 
waste resulting from their disintegration. This material is, owing to the formation of hydrous 
ferric oxides, coloured various shades of red, brown, and yellow. 

The tendency of many of the lavas and the inclusions in the breccias to alter or weather 
spheroidally is an interesting phenomenon, and cores of hard fresh rock enclosed in concentric 
exfoliating lavers are of rather common occurrence. 

The petrography of various rocks of the series is described in detail in two volumes en- 
titled " Rocks of Cape Colville Peninsula,"* and has also been discussed at considerable 
length in the bulletin dealing with the neighbouring Coromandel area. From the same series 
within the Thames Subdivision numerous rock-sections have been cut and examined micro- 
scopically, mainly with the object of correctly mapping the boundaries between the 
older volcanics — the " auriferous series " — and the younger Beeson's Island volcanics — a 
non-productive series. It may be stated that no types other than those described in the 
reports named have been here identified. 

Hornblende-andesites, hvpersthene-andcsites, augito-andesites, and pjTOxene-andesites 
are represented. In the last-named type, which is probably the most common, augite and 
hypersthene occur in approximately equal proportions. 



* ■' Rocks of Cape C!olville Peninsula," 2 voU., 1906, Sollas and McKay. 



24 



The dacites are merely rocks of andesitic type in which quartz occurs as phenocrysts. 
They contain the same ferro-magnesian constituents as the normal andesites. As may be 
expected, there is every gradation between the rocks ranging themselves under the various 
headings. 

The " First Period " volcanics differ from the andesites and dacites of the " Second 
Period " mainly in the character of the matrix or groundmass. The micro-pcecilitic (pilo- 
taxitic) ty'pe of matrix predominates in these " First Period " volcanics, while the micro- 
crystalhne or finely granular matrix is also of frequent occurrence. The hyalopilitic or 
glassy groundmass is seldom encountered in the rocks of the older series : it is common in 
those of the Becson's Island Series. 

The following chemical analyses of the andesites from different locaUties near the Thames 
mining centre are submitted : — 





(1.) 


(2.) 


(3.) 


(4.) 


(5.) 


(6.) 


(7.) 


Silica (SiOj) . . 


50-53 


52-65 


54-10 


55-85 


68-12 


57-15 


52-60 


Alumina (AI2O3) 


20-18 


18-87 


17-95 


15-95 


19-64 


19-26 


18-08 


Ferric oxide (FejOg) 


0-64 


3-28 


2-56 


4-72 


0-56 


1-36 


2-88 


Ferrous oxide (FeO) 


5-54 


4-75 


4-25 


5-67 


0-50 


4-17 


5-11 


Manganous oxide (MnO) 


0-18 


0-15 


0-15 


0-10 


Nil 


0-42 


0-23 


Lime (CaO) 


8-75 


8-80 


9-43 


6-54 


0-38 


7-13 


9-30 


Magnesia (MgO) 


3-39 


4-81 


1-86 


3-33 


0-12 


3-58 


4-24 


Potash (K2O) . . 


0-61 


0-68 


1-54 


0-75 


0-53 


1-10 


1-80 


Soda (Na^O) . . 


2-45 


2-74 


2-01 


2-94 


0-57 


2-88 


2-06 


Titaniimi-dioxide (TiOj) 


102 


1-08 


0-78 


1-15 


0-98 


0-84 


0-66 


Loss on ignition 


6-71 


219 


5-38 


3-00 


8-60 


, , 


1-18 


Sulphuric anhydride (SO 3) 












0-12 




Phosphoric anhydride (PaOg) 












0-10 


. . 


Carbonic anhydride (CO 2) 










. . 


Nil 


2-25 


Water at 100° C. 


. , 




. , 


. . 




0-68 


.. 


Combined water and'organic matter 












1-41 


•• 




100-00 


100-00 


100-00 


100-00 


100-00 


100-20 

1 


100-39 



(1.) Hornblende-pyroxene andesite, from May Queen Mine (No. 6 level), Thames. 
(2.) Pyroxene-andesite, from 32 chains south-west of the mouth of Albumia shaft, 

Thames. 
(3.) Partially altered hornblende - andesite or dacite, from upper part of Tararu 

Creek. 
(4.) Pyroxene-andesite, from Kuranui Mine (battery level), Thames. 
(5.) Propylitised equivalent of No. 4, from Kuranui Mine (battery level), Thames. 

This rock subsequent to alteration has been leached by surface waters. 
(6.) P>TOxene-andesite, from Thames Mine (Moanataiari adit level), Thames. 
(7.) Pyroxene-andesite, from Karaka Mines (low level), Thames. 

The rocks Nos. 1, 2, and 4 were specially examined for barium. No. 2 contained 0-09 per 
cent, of baryta, but the presence of barium was doubtful in the case of the other two speci- 
mens. This determination is of interest in view of the occurrence of secondary barytes 
(BaSO^) in the vugs of certain of the quartz veins. 



25 



(2.) Tertiary Volcanic Rocks of the "Second Period" {BeesorCs Island Series). 

General Statement. — The " Second Period " volcanics, or Beeson's Island Series, consist 
entirely of andesitic or dacitic tuffs, breccias, agglomeiates, and lavas. With these effusive 
rocks are associated dykes of andesite, which in places, however, camiot be distinguished 
from the lava -flows. 

The volcanics of this series cover a relatively great extent of country in the Thames Sub- 
division, and reach in places the actual crest of the main range. This great development 
of these rocks is, from a mining point of view, particularly unfortunate, as no epoch of metal- 
Usation affording payable ore-deposits appears to have been connected with their extrusion. 

In general, the lavas of the Beeson's Island Series are less crystalUne in character than 
those of the " First Period." The fragmental rocks, furthermore, contain a greater proportion 
of heavy agglomeratic material, and are not so well consohdated. Advanced propylitic 
alteration has affected only comparatively local areas in the country covered by these volcanics, 
a feature which stands in marked contrast to the widespread alteration of the rocks of the 
earlier period. 

The contact-line, or old-land surface, between the volcanics of this and the older series is 
in places marked by the occurrence of beds carrying carbonaceous material. In other cases it 
should be stated that, on account of the general similarity in original composition of earlier 
and later andesites, the question of determining more than an approximate boundary often 
baffles solution, even when field-work is supplemented by microscopic study. The problem is, 
as already suggested, of considerable economic importance, since this boundary or contact- 
line between the two different rock-formations marks off an area in which payably auriferous 
veins are known, or may be expected to occur, from an area which has never afforded, and is not 
Ukely to afford, an important payably auriferous ore-deposit. It will be noticed, on comparing 
the maps accompanying this bulletin with those appearing in earlier reports, that the writer has 
referred considerably more of the Tertiary volcanic complex to the Beeson's Island Series 
than have previous investigators. The results of the surface-prospecting operations carried on 
in conjunction with the recent survey of the area afford considerable support to the mapping 
of the geological boundaries here adopted. 

Af/e. — A Miocene age has, in the Coromandel Bulletin, been tentatively assigned to these 
" Second Period " rocks, and no further evidence bearing on the f]uestion has been derived 
from the survey of the area under review. 

Distribution. — By far the most extensive stretch of country covered by the rocks of this 
series has unbroken continuity southward from Mill Creek (flowing into the Whitianga 
Estuary) to and be3'ond the Omahu Stream, which drains into the Thames River on the 
Hauraki Plains. As the maps will show, this long strip of country comprises the greater 
part of the drainage-areas of the Waiwawa, Kauaeranga, Kirikiri, Wharehoe, and Matatoki 
streams, and flanks or overlies the inlier of " First Period " rocks occurring within the valley 
of the Puriri. It will be noticed that the Waiwawa area of these rocks is considered to have 
extension westward beyond the Papakai-Maumaupaki section of the main range into the 
upper valleys of Te Mata, Tapu, and Puru streams. The unconformity between the Beeson's 
Island Series and the " First Period " Series is, at certain points in each of these three valleys, 
marked by carbonaceous beds, which include thin seams of lignite. Further southward, in 
the Kauaeranga Valley, the unconformity at this western boundary appears to be approxi- 
mately fixed by seams of carbonised wood embedded in the breccias near the head of the small 
creek entering the Mangakirikiri Stream some 20 chains south of Otanui Creek. 

Structure and Petrology. — In general appearance many of the " Second Period " flow 
rocks differ Uttle from those described in connection with the older series. Those with the 
glassy (hyalopilitic) type of groundmass, however, have a dense black, somewhat vitreous, 



26 

appearance wUch is seldom observed among those of the older group. Furthermore, this 
particular type of rock, when partially weathered, assumes a pecuhar trachytic appearance, 
a fact which led some of the earUer investigators to regard these rocks as trachytes. 

TufTs, breccias, and agglomerates have very extensive development, and generally show 
a rude stratification. As already remarked, these pyroclastic rocks lack the consohdation 
of those of the preceding group. Angular blocks of lava ranging up to 2 ft., 3 ft., or even 5 ft. 
in diameter are by no means uncommon in the agglomerate beds. Fine-grained tufaceous 
material usually constitutes the cementing medium or matrix, but occasionally small angular 
lapilli fill the spaces between the heavier inclusions. 

The microscopic characters of the rocks of this group have been fully described in reports 
already cited, and the examination of numerous rock-sections cut during the course of the 
present survey has revealed no new types. It is sufficient here to remark that hornblende- 
andesites, hypersthene-andesites, augite-andesites, pyroxene-andesites,* and dacites are 
represented throughout the area. 

Tte chemical composition of these rocks, as may be seen from the various analyses sub- 
mitted in the Coromandel Bulletin, differs but little from that of the " First Period " volcanics, 
excepting that the silica-percentage is, on the average, sHghtly higher in the case of the rocks of 
this younger group. 

(3.) Tertiary Volcanic Rocks of the " Third Period." 

General Statement. — The volcanic rocks of the " Third Period," in contradistinction 
to those of the earUer periods, are acidic in character. They consist of pjTOclastics — pumiceous 
tuffs, breccias, and agglomerates — through which have been extruded flows of massive rhyolite. 

These rhyoUtic rocks are mostly confined to the high country on the eastern border of the 
subdivision, where they overlie or break through a very irregular surface of the older vol- 
canics. The contact-line or unconformity is often marked by the occurrence of earthy beds 
containing carbonaceous material. 

The rhyoUtic tuffs have in places been subjected to propyUtic alteration, which was 
attended with a sparse metallisation of certain zones or pipes, but so far they have afforded 
within this subdivision no payably auriferous deposits, nor is the writer sanguine that such exist. 

Age. — The age of these rocks is usually regarded as Pliocene, and probably rightly so. 
During the course of the present survey, fairly well-preserved fern and leaf impressions were 
collected from the carbonaceous basal tuffs and mudstones of Wainora Creek, Kauaeranga, 
but these have not yet been identified. Casts of the fresh- water mussel {Unio aucklandicus) 
are abundant in some of the mudstone layers in the same locality, and it is interesting to 
note that this same species of shell-fish to-day inhabits the swamps and lagoons on certain 
terraces bordering th.e lower Kauaeranga. 

Distribution. — In the north-eastern portion of the district rhyoHtic tuffs and breccias 
cap most of the country drained by the small tributaries entering the lower and middle course 
of Mill Creek, flowing into Whitianga Estuary. Seams of coaly material at certain locaUties 
mark the miconformity between these and the imderlying rocks, but such seams are of Kttle 
economic importance. The rhyoHtes are continuous south-west from here to Waimahoe Creek 
and eastward beyond the limits of the area examined. Further southward they are again 
met ^nth here and there in the vicinity of the eastern boundary of the subdivision. Sur- 
rounding the Table Mountain andesitic intrusive, there exists the remnant of a formerly fairly 
extensive rhyolitic plateau of fragmental and massive rhyolites, through which the streams 
cut deep narrow gorges. Seams of poor Hgnite occur in places at the basal unconformity. 
This old volcanic plateau extends from Table Mountain eastward and southward along the 
high country drained by the eastern tributaries of the Kauaeranga. 

* Pyroxene-andesites : Those in which the hypersthene and augite are present in almost equal proportions. 



W'^^'' 









;•<* 



'5/^^i>^«i 




ANDKSITK DyKK IXTKliSKtTINc; ){EI:sON's Isi.VM) Vni.CANICS. KALAKKAXliA 

Vai.i.ky, Thames. 
Dvke rock shows well-marked jointing. 



liiiUctin Xo. 10.] 



[Face p. 26. 



27 



In the southern portion of the subdivision a tongue-shaped area of rhvoHtic rocks sweeps 
in from the Tairua Survey District, and forms the high country drained by the headwaters 
of the Kirikiri, AMiarehoe, and Matatoki streams, and also caps the andesitic country in parts 
of the Puriri Valley. A smaller area forms a stretch of the foothills skirting the Hauraki 
Plains just northward of Hikutaia. 

Structure and Petrology. — Fragmental rocks — tuffs, breccias, and agglomerates — are 
by far the most abundant members of this series, and through these beds the lavas were 
extruded at various points. The lava plugs which filled the conduits have in certain cases 
been laid bare and isolated by agencies of denudation, and now form prominent features 
of the landscape. The Twin Peak in the upper Puriri is one of the best exam|)les of these 
plugs. 

The fragmentals, which are in general of creamy-white colour, vary in character from 
tufaceous mudstones to fairly heavy agglomerates, but the predominant tj-pe is a fine-grained 
tufaceous agglomerate, in which the larger isolated fragments of flow rhyolite rarely exceed 
I in. in diameter. Pumice is a common constituent of this and of all the other fragmentals. 

The beds are disposed horizontally, or dip at low angles. The predominance of inclina- 
tions at low angles to the south-eastward is indicative of a regional tilting of the whole land- 
mass in this direction subsequent to the Pliocene eruptive activity. 

The weathering of these rhyolitic fragmentals, which usually contain few joints, frequently 
gives rise to rather bizarre land-forms. Vertical scarp-faces and outlying stacks are not 
uncommon : these white walls of rock, frequently scored with vertical flutings or corrugations, 
recall famiUar topography in limestone country. 

The petrography of the rocks of this series is described in previous reports, and detailed 
reference to it here is unnecessary. The massive rhyolites of the area usually show a marked 
banding due to flowage, and frequently exhibit spherulitic structure. The massive rhyolite 
of the Table Mountain Range consists mainly of what is almost isotropic (glassy) material, 
enclosing numerous trichites (hair-like crystals). Scattered throughout this groundmass 
are shreds and plates of biotite and a few isolated phenocrysts of orthoclase. The rock of 
the Twin Peak (Puriri) and other localities differs little from this type. A chemical analysis 
of a similar rhyolite cited in the Coromandel Bulletin reads as follows : — 

Silica (SiOa) . . . . . . . . . . 72-40 



Alumina (ALOj) 
Ferric oxide (FejOj) 
Ferrous oxide (FeO) 
Manganous oxide (MnO) 
Lime (CaO) 
Magnesia (MgO) 
Potassium-oxide (KjO) 
Sodium-oxide (NajO) 
Titanium-oxide (TiOj) 
Carbonic anhydride (CO^) 
Water and organic matter 



14 09 
0-48 
2-52 
0-42 
115 
0-20 
4 09 
2-97 
015 
0-82 
0-86 



Total 



10015 



(4.) Intrusive Rocks of Various Periods. 
General Statement. — Intrusive igneous rocks representing a considerable range in time 
have development in the Thames Subdivision. They are associated with each of the two 
series of sedimentary rocks, and with the Tertiary effusive rocks which overlie these sedi- 
mentaries. These intrusives are all semi-basic or intermediate in character, and consist of 
diorites, porphyrites, dacites, and andesites. 



28 

Age. — It is certain that most of these intrusives are referable to one or other of the periods 
of Tertiary vulcanism, but it is not improbable that certain of the dykes associated with the 
oldest group of sedimentaries — the Tokatea Hill Series — may, as pointed out in the Coro- 
mandel Bulletin, belong to an early Jurassic or a pre-Jurassic period. The enormous amount 
of igneous detritus which has contributed to the formation of the Upper Jurassic conglomerates 
is certain evidence of an ancient period of widespread vulcanism. 

Distribution and Petrologij. — In the upper Manaia Valley the argiUites and the interbedded 
felsitic tuffs are, as in most areas where such rocks are developed, intruded by numerous dykes. 
The prevaihng intrusive rocks are hornblende-porph}Tite and hornblende-andesite, the latter 
type in some cases having a dacitic facies. These rocks are in general of greyish colour, and 
obviously porphjTitic. The contact metamorphism attendant upon their intrusion has been 
very local, and comparatively slight. 

Within the exposure of Jurassic strata extending southward from near Kirita Bay to 
Te Mata Stream no intrusives were observed other than those exposed on the coast-Une be- 
tween the mouth of the stream named and the Waikawau. Here a series of dykes ramifpng 
throughout the strata are conspicuous features, and have been the subject of several geological 
notices. None of these intrusives appear to be exposed further inland, although the largest 
of them measures about 10 chains in width. The rocks are usually markedly porph}'ritic, 
and range from greenish-grey to black in colour. Microscopic examination has shown that 
they range from hornblende-andesite to hornblende-hypersthene andesite, ■with occasionally 
transitions towards a dacitic facies. 

Associated with the " First Period " volcanics at the second point on the coast-Une 
north of the mouth of Waiomo Creek, is an exposure of fine-grained greenish-grey rock, from 
which a specimen was collected by McKay and identified by Sollas as an " augite-diorite," 
with hypersthene and a httle quartz and orthoclase.* " This," Sollas remarks, " is a very 
interesting rock, and provides us with the holociystaUine equivalent of the hypersthene- 
andesites. A complete series thus exists in the district, extending from hypersthene-augite 
diorite to andesitic glass." 

It is certain that numerous dykes exist in the Tertiary andesitic complex, but, owing 
to their general similarity to the effusives, they cannot with any certainty be differentiated. 
Boring operations at Thames showed the existence of numerous dykes of andesite intersect- 
ing the sedimentary rocks of the Tokatea Hill Series, which underUe at a depth of 1,170 ft. 
the andesitic formation, and some of these may reasonably be expected to persist above the 
basement rocks. 

By far the most interesting and conspicuous dyke in the whole peninsula is that forming 
the Table Mountain, between the headwaters of the Kauaeranga and Waiwawa rivers. It 
consists of hypersthene-andesite, and, being intrusive into the PHocene rhyolites, constitutes 
probably the youngest igneous rock in the district. The agencies of denudation have not 
yet succeeded in greatly modifying the form of this massive dyke, nor in completely removing 
the surrounding less-resistant rhyohtes which it protects. The Table Mountain proper is 
about half a mile wide, and on three sides presents nearly vertical cliffs of 400 ft. to 800 ft. 
in height. Its elevation is approximately 2,800 ft. 

Separated from the mountain itself by a depression which a small headwater branch 
of the Waiwawa has cut in the flanking rhyohtes is the north-westerly trending steep-sided 
Table Mountain Eango. The south-western side of this range, which presents bold precipi- 
tous faces, consists of a belt of the same andesitic dyke rock. The south-eastern side, which 
is the least precipitous, consists mainly of a remnant of the massive and fragmental rhyolites 
of the ancient plateau which the dyke rock intersected. 



'■ " Bocks of Cape Colville Peninsula," vol. i, pp. 236-237. 



29 

This dyke rock exhibits a fairly regular pentagonal columnar jointing, the columns being 
set nearly at right angles to the walls or cooling surfaces. Fragments of these columns are 
readily recognised in the stream-debris of the Waiwawa and the Kauaeranga, miles away from 
the mountain. 

In appearance, the rock forming this gieat dyke is black, compact, somewhat lustrous, 
and shows large phenocrysts of glassy colourless plagioclase. It has been determined by 
Sollas as a hyalopilitic quartz-hypersthene andesite, the phenocrysts being disposed in a 
matrix consisting, in the main, of clear brownish glass. 

The same Table Mountain intrusive andesite appears again in the valley of the Hihi 
immediately eastward of the area mapped. Further southward in Ruapekapeka Creek, 
Puriri Valley, a dense black lustrous hypersth3ne-andc5ite, which appears to be intrusive into 
rhyolites, is probably referable to the same period. 

Loosely Consolidated and Unconsolidated Debris. 
The deposits coming under this heading may be grouped, according to age, as («) Late 
Pliocene or Pleistocene deposits, (6) Recent deposits. 

(a.) Late Pliocene or Pleistocene Deposits. — Deposits coming imder this heading form high- 
level river-terraces and raised sea-beaches, and ])robably constitute part of the deeper-seated 
alluvium which has tilled in the submerged grabeti of the Firth of Thames. 

The high-level river-terraces consist of rudely stratified clays, sands, and gravels, with 
which are intermingled large boulders of solid andesite, rhyolitc, and <|uartz. 

These terraces have development at Thames, between Waiokaraka Gully and Hape 
Creek, crossing Irishtown, and Block XXVII. Their maximum height here is about 150 ft. 
South-westward from Hape Creek they continue to skirt the base of the hills to the lower 
part of Kauaeranga \'alley. From the south side of the Kauaeranga they form the downs 
skirting the higher country and bordering the plains to and beyond the locality where the 
Kirikiri Stream debouches. For some distance up the Kauaeranga Valley, too, terraces rise at 
many places above the lower alluvial flats. 

North of Thames a remnant of the old Tararu Terrace is still preserved on the south side 
of tho Tararu Stream, and a similar patch of the old Otakeo Terrace occurs on the coast north 
of Waikawau. 

Raised sea-beaches are exposed at several localities on the coast-Une between Thames and 
Waikawau, and notably near the mouth of Otohi CVeek, where they attain an elevation of over 
25 ft. It has already been remarked that at Miranda, on the opposite side of the Firth of 
Thames, old beaches elevated 10 ft. or 12 ft. above present high-water mark are common. 

(b.) Recent Deposits. — The extensive deposits of the Thames-Piako Plain (Hauraki 
Plains), extending from the Firth of Thames to the southern limits of the area mapped, are 
alone worthy of special nibution. Away from the base of the hill country rising from the 
eastern margin of this plain, and away from the influence of the streams draining this elevated 
country, the deposits of the plain comprise pumiceous sands, muds, loam, and peaty material. 
It is generally believed that much of the alluvium which has reclaimed the deep graben area 
of the Firth of Thames is referable to a river of considerable volume — probably the Wai- 
kato, which formerly discharged into tho Hauraki Gulf. As shown by boring, the depth 
of the alluvium just oil the original coast-hno at Thames probably e.xceeds 1,100 ft. Little 
or nothing is recorded as to the nature of the deeper deposits penetrated in this bore. It 
is stated generally that they consisted of sands and muds, and also that trunks of trees were 
occasionally encountered. " At Turua (near the Thames River) the remains of an old forest 
were met at a depth of 30 ft., clearly indicating a recent subsidence of land."* 



♦ " Geology and Veinfl of the Hauraki Goldfield," Park, p. 42. 



30 



Regional Earth-movements and Faulting. 

An inspection of the geological map of the Thames Subdivision, or, better still, of a map 
covering the whole Hauraki Division, will show that to the north and west the basement 
sedimentaries have their greatest development, and then follow to the east and south, in order 
of age, the three series of Tertiary volcanics. As might be expected, outlying areas of the older 
Tertiary igneous rocks surrounded by the younger rocks do occur, but the statement regarding 
the general disposition still holds good. 

The disposition of the rock-masses as a whole, and of the members of certain of the in- 
dividual series, register^ a tilting movement of the whole Hauraki land-mass on a north- 
east axial Une, connecting Rocky Point on the western coast-line with Kuaotunu on the eastern 
coast-line. The area north-west of this line has undergone elevation ; the area to the south- 
east, depression. The basement sedimentary rocks are not visible south of this Rocky Point- 
Kuaotunu line. 

This compensating movement of elevation in one part of the area and depression in another 
appears to have begun in an Early Tertiary period, and has certainly continued to comparatively 
recent times, if, indeed, it is not still in progress. Raised sea-beaches are common on the 
north-western coast-Hne ; sunken-river mouths, cut in the Phocene rhyolites, are conspicuous 
on the south-eastern coast-Une. 

The conditions indicated have a direct economic bearing, especially in respect to the 
depths to which the vein-bearing volcanic rocks in certain of the mining areas are likely to 
persist. 

The dislocation of rock-masses by faulting has been shown by the mining operations 
of almost every locality to be a common feature. Owing to the comparative homogeneity 
of the enclosing rocks, and their proneness to weathering, the existence of few of these faults, 
however, can be inferred merely from an examination of the surface. 

The origin of the faulting in an area which gives evidence of widespread earth-movements, 
and which has been the scene of intense volcanic activity at several different periods in the 
Tertiary era, is not far to seek. Upward and lateral thrusts of the crust due to violent migra- 
tions of rock magma can be postulated ; so also can subsidences due to the weakening of the 
basement following the transference of great quantities of material from considerable depths 
to the svirface by volcanic agencies. Reversed or thrust-faults and normal or tension-faults 
are thus explainable, and occur frequently. 

The Moanataiari Fault. — Of all the faults in the area the Moanataiari is certainly the 
most conspicuous. It occurs in the heart of the mining centre of Thames, striking transversely 
to the trend of the reefs, and is traceable from the Hape Creek in the south to and beyond 
the Shellback Creek in the north. Its hade or underlie is to the south-west — that is, towards 
the harbour — at an almost uniform angle of 45°. 

This remarkable fault gives considerable topographical expression to the land-surface, 
its course being marked by a distinct scarp bordered by an area of depression. As the contour 
map of the Thames special area will show, the spurs or ridges which it crosses rise fairly abruptly 
on its upland side to a height of 300 ft. or 400 ft. above the general level of the corresponding 
portions of the spurs on its downthrow or seaward side. 

A characteristic fault topography is also imprinted on the valleys of the several streams 
which the fault crosses, the downthrow having brought a wide part of each valley in juxta- 
position to a narrow part. On ascending any one of the streams, therefore, the valley is 
wide and open until the fault is reached ; here it contracts to a narrow gorge, and the stream- 
bed shows for some distance a markedly steeper gradient. In all the streams except the 
Shellback the waterfalls, which in all probability existed, have been obliterated by the great 
amount of debris which completely fills the beds of the valleys from the fault-scarp seaward. 




Tin; MoAXATAi Alii 1''ali,t-sc'ai<i", J'iiamks. 
View lodkinj; scmtliwai d lioni spin botwci'ii Shellback C'let'k and Sholovcr Creek. 



Hull, till So. in.] 



[Ff/rc [,. ;ill. 



31 

In the Shellback, however, a waterfall of about 90 ft. in height has been gradually cut back 
by the stream from the point where the fault crosses the valley. 

The fault-fissure itself, as seen in the various mine-workings, usually contains a con- 
siderable thickness (20 ft. to 40 ft.) of crushed rock and compressed gouge or clayey material. 
Furthermore, the wall-rocks on each side are frequently shattered for some distance. It is 
recorded that in places the fault-fissure contained loose-running sandy material, and in others 
fragmental rock so hard that explosives had to be employed in penetrating it. 

The magnitude of the downthrow of this fault is difficult to determine accurately owing 
to the absence of any well-marked geological horizon. The difference of altitude of the spurs 
on each side of the scarp — 250 ft. to 350 ft. — indicates a vertical displacement — making due 
allowances for modification by denudation — of, say, 400 ft. It is believed by the writer 
that the surface configuration as described registers the last great movement rather than 
the total movement along this fault-plane. As the question of the total amount of downthrow 
is one of considerable importance, its solution was sought from a calculation based on the 
offset of the Waiotahi-Cambria reef as exhibited in the nearest mine-workings on each side 
of the dislocation. This calculation gave 595 ft. as the downthrow in the Waiotahi Creek 
locality. It is satisfactory to note that Mr. E. F. Adams, mining engineer, postulated some 
years ago, as the result of a calculation based on the offset of the Caledonian No. 1 reef, a 
downthrow of about 600 ft. It seems probable that a shearing movement along the fault-plane 
took place, and that the magnitude of the downthrow is less than 600 ft. northward, and 
greater than 600 ft. southward of Waiotahi Creek. In the southern end of the field the effects 
of the Moanataiari fault and of the Collarbone fault, which meets it in the lower part of Karaka 
Creek, are Ukely to have been cumulative. Probably the downthrow in the vicinity of Una 
Hill may approach 1,000 ft. 

The Collarbone Fault. — A distinct line of depression is noticeable to an observer looking 
from the Shortland Flat up the Collarbone Gully and across the Waiotahi Valley to a point 
hillward of Alburnia shaft. Landslips and soft crushed rock are conspicuous at various points 
along this line. Mine-workings, however, where the fault should have been encountered 
show only minor dislocations and also heavy clayey selvages along the hanging-walls of certain 
of the stronger veins. The Waiotahi-Cambria reef, however (known here as the Golden Age), 
outcropping at an elevation of 1,100 ft. to l,2fX) ft. near the Ruby low level, appears to show 
a considerable offset. In the writer's opinion the existence of the Collarbone line of faulting 
must be admitted, but in many places it consists probably of a zone enclosing a number of 
parallel, linked or overlapping, displacements rather than, as in the case of the Moanataiari, 
a single strong fault-fracture. 

The Beach " Slide " or Fault. — The Beach " slide " terminates to the westward the vein- 
bearing rock underljnng the foreshore flat at Thames. Seaward of this " sUde " the muds, 
sands, and gravels of the harbour are encountered. In the workings of several of the mines 
the veins have been followed at different levels right out to this depressed land-scarp, which has 
been proved to descend at angles approximating 45°. These workings have also shown that 
its trend corresponds to some extent with the windings.of the cliffs in the rear of the township 
flat. In certain drives which have reached the "slide" a band of gouge or clayey material 
similar to that filUng many fault-fissures has been found interposed between the solid rock 
and the alluvium. Quoting from a former geological report,* " At Nos. 1, 2, and 3 levels 
of the Prince Imperial, and at No. 7 level of the Piako shaft, a large reef from 8 ft. to 14 ft. in 
width was found to run along the course of the Beach ' slide,' lying on and forming the old 
floor of the harbour. Mr. G. S. Clarke states that ends of the reefsf as they approach the 
' shde ' bend to one side, as they do on approaching the Moanataiari fault." 



* " Geology and Veins of the H.iur.aki Goldfield," Park, p. 66. 
f I.e., the more or less transverse reefs. 



32 

Further and more recent evidence bearing on the nature of this " slide " is that derived 
from boring. A borehole sunk by the Victoria Company at a point only 13 chains west of the 
old Big Pump shaft failed to find solid country at a depth of 1,120 ft. This not only shows 
a very considerable depth of alluvium, but if the bore has continued down vertically, it indicates 
that the slide persisted downwards at a very high slope-angle. 

The evidence available is inconclusive as to whether this is a fault-scarp or merely an 
old steep-sided depressed shore-hne. In the writer's opinion, however, the very high slope- 
angle, apparently persisting to a very considerable depth and associated with easily eroded 
propylitic rocks, is strong evidence in favour of the existence of a fault. So also is the large 
reef reported as following the course of the " slide," and the peculiar bending of the transverse 
reefs as they approach the " slide." 

Some of the mine-managers consider that the conforming of the Beach " slide " to the 
contours of the existing gullies proves that no fault ever existed, but, as pointed out by Park, 
this " would only show that a certain amount of denudation took place in the gullies crossing 
the line of fault before the filling of the harbour took place." 

The Firth of Thames and its former prolongation — now the low-lying plains of the Thames 
Valley — is apparently, as regarded by Lindgren, Maclaren, Park, Morgan, and others, a 
graben or downfaulted area, and the WTiter believes that both the Moanataiari fault and the 
Beach " sUde " or fault are dislocations connected with its formation. 

Minor Faults. — The many small faults and cross-courses which mining operations have 
shown to exist call for no special comment here, but will receive notice in other sections of this 
report. 



33 



CHAPTER V. 



MINERAL VEINS AND CONDITIONS IN MINERALISED AREAS. 





Page 


Structure of the Vein-material 


.. il 


Oxidation 


.. 42 


The Ore-deposits 


.. 42 


Undergrounil Temperatures 


.. 45 


Underground tiases 


.. 47 


Underground Water 


.. 48 



Page 

Periods of Mineralisation . . . . 33 

The ^'ein Fissures . . . . . . 33 

The Mineralising Agents . . . . 34 

Rock-alteration connected with Mineralisation 34 

Mineralogy of the Vein-minerals . . . . 36 

Non-metallic Minerals . . . . . . 36 

Metallic Minerals . . . . . . 37 

Periods of Mineralisation. 
The quartz veins of the Thames Subdivision are referable to three more or less distinct periods 
of mineralisation, but only among those formed during the first or earliest of these periods 
have payably metalliferous veins been found. 

The oldest and the commercially important veins are, in the main, associated with the 
Tertiary volcanic rocks — andesites and dacites — of the " First Period," but are also found 
in the Jurassic and pre-Jurassic sedimentaries. The productive mining country imme- 
diately behind the Town of Thames terminates with conspicuous abruptness on the south- 
eastern side of Hape Creek. Here younger andesitic rocks (Beeson's Island Series) flank 
the older volcanics, and are entirely devoid of quartz veins ; hencethe marked mineralisation 
of the Thames centre evidently preceded the eruption of the younger volcanics. 

To the second peiiod of mineralisation apparently belong certain quartz veins and 
silicified bands in the younger andesitic rocks of the Waiwawa and the Kauaeranga valleys on 
the eastern side of the subdivision. Although the thermal waters which followed the e.xtru- 
sion of these andesites have here effected considerable propylitic alteration of the rocks, 
they appear to have been strikingly deficient in gold and silver, and the veins formed during 
this period are practically barren. 

To the third peiiod of mineralisation are referable certain silicified bands and pipes 
and a few poorly defined chalcedonic quartz veins occurring in the tufaceous rhyolites of the 
eastern portion of the area. Certain of these carry small gold-silver values, but so far they 
have proved unimportant. 

The Vein Fissures. 

The openings in the rock which afforded channels for the circulation of the mineralising 
solutions, and formed the depositaries of the vein-materials, were either fairly well-defined 
fissures or complex fractures of rather poor definition and little persistence, or, again, the 
innumerable small fractures afforded by sheeted or brecciated zones. 

A conspicuous feature of the quartz veins of Thames, and, in fact, of the whole Hauraki 
area, is their predominating north-east - south-west .strike. It is difficult to ascribe local 
causes to account for this phenomenon, and it may be in part an expression of the crumphng 
and attendant fracturing of the rock-masses parallel with the Ruahine-Alpine line of New 
Zealand folding. That movements which effected folding of strata along this north-east - 
south-west axial Une were repeated again and again in Tertiary times there is ample evidence.* 

* Bulletin No. 6, N.Z. G.S.. Mikonui Subdivision (Morgan) p. 37. 
3— Thames. 



34 

The main line of folding iu the North Auckland Peninsula and in the subsidiary Hauraki 
Peninsula is. it may be mentioned, nearly normal to and is generally regarded as older than 
the Ruahine-Alpine line. 

Some of the fissures, and particularly those of greater persistence, show evidence of fault- 
movement. Such faulting along sinuous and contorted fissures has afforded openings which 
have given rise to the markedly lenticular arrangement of the veinstone observable when 
traced either in strike or in dip. The Waiotahi-C'ambria reef at Thames, for example, may 
be over 30 ft. wide in a particular cross-section and gradually diminish in a comparatively 
short distance to a foot, beyond which point it may open out again as before. A clayey 
sUckensided gouge or " dig " often accompanies the veinstone of Thames reefs, but this not 
infrequently represents post-mineral faulting. 

In addition to any regional tension which may, as previously stated, have effected the 
rocks of the area, contraction due to the coohng of eruptive material and stresses caused by 
latent volcanic energy probably contributed to the formation of the fissures. 

In connection with, the numerous veins at Thames it may be stated that the rock-frac- 
turing wliich determined their positions has been extremely complicated. Although general 
lines of reef-systems may be recognised, it is very often impossible to trace a particular vein 
for any considerable distance imless identity is actually established by connected mine- 
workings. A vein may persist a certain distance, and gradually feather-out : beyond this 
point the approximate line of fracture may be taken up by another vein some distance in 
the offset. Again, complications may arise from the intersection of cross-veins or branch 
veins, as well as from numerous non-mineralised cross-courses and faults. The fissures 
naturally vary in character according to the nature of the rocks they intersect. In the 
altered massive andesites they are usually much better defined than in the altered breccias. 
In unaltered dark andesite the fissures which do persist are invariably more contracted in 
width than in the softer altered rock. Many of the weaker fissures, however, spht up and 
die out completely on nearing or entering the larger belts or remnants of hard rock. 

Mine-workings have made it quite apparent that the vein fissures near the surface greatly 
exceed in number those occurring at greater depths. Many of the parallel veins, apparently 
quite independent at or near the surface, on being followed downward terminate on the hang- 
ing-wall of the larger and more persistent reefs, and are therefore generally termed " hang- 
ing-wall droppers." 

The Mineralising Agents. 

Aqueous solutions were evidently the mineralising agents which afforded the vein-material 
deposited in these fissures. The character of the veinstones and the nature of the alteration 
of the wall-rocks give some clue as to the composition of these solutions. That the waters 
were hot and, in the main, ascending there is little reason to doubt. They were evidently 
an accompaniment of the " eruptive after-actions " — the periods of solfatarism — which 
marked the closing phases of certain manifestations of vulcanism. 

R0CK-.\LTERATI0N CONNECTED WITH MINERALISATION. 

At Thames, as in other andesitic goldfields, the profound alteration of the andesitic and 
dacitic rocks, especially in the vicinity of the veins, is a characteristic feature. The character 
of this rock-alteration in its advanced or final stage is usually described as " propylitic," using 
the term as defined by Rosenbusch. Hard dark-bluish andesite (" blue metal " of the miners) 
has been changed by hydrothermal agencies to a comparatively soft, granular-looking, pyritised 
rock of white, greyish-white, or bluish-white colour. This altered andesite or propylite, 
probably owing to its granular appearance, is usually termed " sandstone " by the miners. 
Tuffs and breccias have imdergone a similar alteration, and the resultant rock is in places 
difficult to distinguish from a completely altered massive andesite. 



35 

An examijiation of completely altered andesite (propylite) under the microscope shows 
that the feldspars are replaced by carbonates and sericite, with occasionally secondary quartz. 
The ferro-magnesian minerals, which invariably pass through a stage of chloritisation, are 
finally replaced by carbonates, magnetite, and sometimes quartz granules. Pyrite, which is 
scattered throughout the rock as cubes and granular aggregates, generally replaces original 
magnetite, but not infrequently occurs as nests in the places formerly occupied by ferro- 
magnesian minerals. Leucoxene, as an alteration-product of titaniferous minerals, is in small 
quantities not uncommon. It has been pointed out by Finlayson* that much of the greyish- 
brown opaque masses which in Hauraki rocks appears to have been frequently referred to 
leucoxene is in reality the carbonate, siderite. Epidote is rather sparingly present iji the 
altered audesites of Thames, and in this respect mainly they differ from Rosenbusch's type 
rock. 

A fairly i-egular transition from the softer light-coloured propylite to the hard, dark, 
imaltered andesite can be observed in some of the mine-workings. The rock of the in- 
tervening stages is in general of a dirty greenish colour, varying hardness, and is sparsely 
pjTitised. The partial alteration which it has undergone has resulted mainly in the develop- 
ment of greenish chlorite and, in less degree, of carbonates and sericite. Such country rock is 
invariably non-productive. 

Gradual transitions from propylite to hard andesite are, however, not always recognisable. 
Occasionally a mere puggy seam or a narrow fracture will separate propylite from hard 
country. Again, core-like remnants of hard andesite — locally designated "boulders" — may 
be found within the propylite. The occurrences of such " boulders " are common in the slopes 
on certain veins in the May Queen Mine, and are analogous to the cores due to concentric 
weathering in many surface rocks. 

One of the better defined of the " hard bars " of the Thames field is the dyke-like rem- 
nant of unaltered andesite in the country separating the two parallel reefs, Reuben Parr and 
Golden Age, on the south side of the Moanataiari Valley. Some of the " hard bars " of the 
field have been proved by mine-workings to be simply " Hoatcrs" — lensoid remnants enclosed 
in altered rock — while others have persisted to the greatest depths reached by mining explora- 
tion. 

It is generally considered, and probably rightly so. that rock-fracture affording vein 
fissures hiis, in the main, preceded the propylitic alteration of the andesitos. In other words, 
the vein fissures are regarded as the focal planes from which thermal water and vapours 
were diffused throughout the wall-rock. Proof of this is affordini by the " hard bars," which 
have been mentioned as frequently occurring in the country rock separating two paial!el 
reefs. 

The peculiar feature of many of the Thames roofs vcoring away in strike from the larger 
belts of hard country, or of splitting up suddenly and dying out on approaching such belts, 
is noticeable. This variation in strike or the complete termination of such vein fissures may 
be held to be the cause rather than the effect of the existence in these particular positions of 
such belts of unaltered rock. Such a view is rather difficult to accept, especially in the 
case of a great portion of the Thames mining centre, where a single comparatively homo- 
geneous mass of andesite formed the original rock-mass. The idea suggests itself that many 
of the vein fissures may not have been formed ujitil alteration to a considerable degree had 
been effected by hydrothermal solutions. Any fissures subsequently formed would ten<J 
to follow the lines of least resistance — that is, they would intersect the softer altered rock 
and avoid resistant belts or remnants of hard rock. That some of the breccia - beds 
were, prior to the formation of the vein fissures, well consolidated, considerably altered, and 



* "Problems in the Geology of the Hauraki Goldficlds, New Zealand," Finlayson, A. M., "Economic 
Geology,"' vol. iv, No. 7, 1909. 

3* — Thames. 



36 

thus rendered, relatively homogeneous, appears evident from the clean-cut form of many of 
these fissures. Penrose has expressed this opinion in regard to certain of the vein-bearing 
breccia-areas of Cripple Creek, U.S.A. 

Within a p}Titised propyUtic rock-mass the practised eye can detect various shades of 
alteration, which are difficult to actually describe. Hence the miner discriminates between 
the favourable " kindly " or " lively " country and the unfavourable " dead," '" motley," 
or " shingley " country. 

In the case of the few veins intersecting the old argiUites and grauwackes (" slates ") of 
the subdivision, only sUght alteration of the wall-rock is noticeable ; the interstratified 
" felsitic " mudstones, however, assume a hght colour, and are highly p^Titised. In the 
case of the fine-grained Jurassic conglomerates, however, so much audesitic and rhyolitic 
detritus is contained in the rocks that hydrothermal alteration renders the mass difficult 
to distinguish from a propyhtiscd andesitic breccia, and for the latter rock it has frequently 
been mistaken. 

Mineralogy of the Veix-minerals. 

Tlie minerals commonly met with in the veins of Thames are few, though a hst covering 
all the occurrences that have from time to time been identified is somewhat lengthy. 

Quartz and, to a less extent, pyrite constitute the main gangue-minerals of the gold- 
silver veins. Calcite in small quantities is not of infrequent occurrence. The presence of 
rhodonite and rhodochrosite. the silicate and carbonate of manganese, is characteristic of 
much of the veinstone of the lower Tararu Creek valley. 

The minerals galena, zinc-blende, and chalcopyrite generally occur in close association 
and are fairly abundant in the ore-shoots of the Sylvia and Waitangi claims at Thames, and 
of the Monowai and other claims at and near Waiomo. The presence of these sulphides, 
though usually in smaller quantities than at the localities cited, is evident in many of 
the minor veins traversing the country Mng between* Kuranui and Tapu creeks. 

The minerals detected from time to time during the course of mining operations have 
been the subject of many notices, and on such notices the writer of this report has largely 
drawn. 

Non-metallic Minerals. 

Quartz. — Quartz, the most abundant gangue-mineral in all the veins, occurs both as 
fissure-filling and to less extent as the result of sihcificaticn of the wall-rocks. It is gene- 
rally finely crystalhne, or, again, is crystalhzed as small prisms terminated by pyramidal 
faces, the colotir in either case being white or bluish-white. The markedly \atreous lustre 
which characterizes most of the vem-quartz in the older rocks of the South Island of New 
Zealand is absent in the quartz of Thames. Quartz exhibiting the platy and other structures 
attributable to replacement after calcite is here not of common occurrence, as it is in the 
Ohinemuri and Kuaotunu goldfields of Hauraki. 

Amorphous and Cryptocrystalline Silica. — Chalcedony and jasper are common in veinlets 
in the argilhtes and also as veins and nests in the volcanic rocks, particularly the rhyolites. 
Sihceous sinters, as pipes and sheets, have considerable development in the area extending 
eastward from Look-out Rocks to the Kauaeranga River. Wood opal (silicified wood) and 
common opal occur in the areas consisting of rhyolite or of '" Second Period " andesite. 

Calcite. — Calcite is frequently found in quartz veins as rhombohedra. scalenohedra, 
hexagonal prisms, and various modifications of these forms. Certain veins in AVhalebone 
Creek consist almost entirely of calcite ; elsewhere it is present in relatively small quantities. 

Aragonite.- — Aragonite, as white transparent prismatic crystals (Eldorado Claim. 1869 ; 
Hutton). 



37 

Selenite (Gypsum). — Seleiiite, as beautifully crystallized specimens (Skey, 1870-71). Pris- 
matic crystals of this mineral were collected from the Moanataiari tunnel. 

Witherite (Barium-carbonate). — Occurrence reported (Thames, 1870-71 : Skey). 

Barytes (Barium-sulphate). — Barytes has been identified in many of the mines as trans- 
parent thin plates and rhombic prisms, the latter often attached by their edges to the exterior 
of the quartz or pyrite. It is generally found in vugs in the veins. 

Pearlspar, or Ankerite. — Ankerite containing carbonate of iron along with the carbonates 
of calcium and magnesium is of common occurrence in certain veins of Una Hill and Karaka 
Creek, and is occasionally seen elsewhere. The mineral is generally found in the central drusy 
parting of the veins. 

Epsomite. — Epsomite, the sulphate of magnesia, is noticeable in considerable cjuantities in 
the Waiotahi, Kuranui-Caledonian, and other mines, generally in the warm old workings, 
where it hangs in festoons from the roof and sides of the drives. It is referable to the 
alteration of the wall-rock rather than of the veinstone. 

Chlorite. — Chlorite, a silicate of aluminium, with ferrous iron and magnesium, occurs 
with more distinctive character than usual in the damper crevices of the white tufaceous rock 
some distance up Tararu Creek. 

Stilbite. — Stilbite, a hydrous silicate of aluminium, calcium, and sodium, one of the zeolite 
family, has been detected as forming sheaf-like aggregates in cavities in the rhyolites of the 
upper Kauaeranga. 

Garnet. — Garnets are reported to have been found in Karaka Creek (Cox, 1882). 

Fuller's Earth. — The existence in workable quantities of the mineral commonly known 
as fuller's earth was reported from Ohio Creek, Tararu. FuUer's earth, when pure, has, 
according to Kutlcy, the percentage composition : Silica, 45 ; alumina, 20 ; water, 25. The 
material worked in Ohio Creek yielded on analysis : Silica, 51-80 per cent. ; alumina, 33-17 
per cent.; iron-oxides, 0-93 percent. ; lime, 0-85 per cent. ; magnesia, 0-45 per cent. ; alkalies, 
2-25 per cent. ; moisture, 1-70 per cent. ; organic matter, 8-85 per cent. : total, 100. It is 
therefore an impure clay, and has evidently been derived from an altered audesitic rock. 

Kaolin. — An undetermined kaolinitic material — the " pug " of the miners — is fairly 
abundant in the veins. In part it probably results from the decomposition of the felspathic 
constituents of the wall-rocks and in part from an extremely fine comminution of the wall- 
rocks along planes of movement. 

" Silica." — A white or creamy-white fine-grained powdery material, locally termed 
" silica," frequently occurs in vugs and cavities in the (juartz veins of Thames, and is 
generally regarded as a good indicator for gold. An analysis of a sample of this material 
from the Waiotahi Mine gave : Silica (SiO,), 89-10 per cent. ; alumina (AI^Oj), 4-84 per cent. ; 
iron-oxide (Fe^Oj), 0-78 per cent. ; hme (CaO), 1-03 per cent. ; magnesia (MgO), 0-70 per 
cent. ; potash (KgO), 1-10 per cent. ; soda (Na^O), 0-12 per cent. ; loss on ignition, 113 
per cent. ; carbon anhydride (CO,), nil ; undetermined, 1-20 per cent. : total, 100. 

Mellite (AljCjg^io + ^^ HjO). — A resinous-looking substance with spUntery fracture, 
collected by Hutton, was considered to be the hydrous aluraiuium-mellite. (Hutton : 1870.) 

Metallic Minerals. 

Gold. — The gold of this field occurs in alloy with silver as an electrum, and to a minor 
extent in a few localities as auriferous tellurides. The gold-fineness of the electrum from the 
various claims varies from about 0-6250 to 0-7500, and in the case of the VV'aitangi Claim, 
where the electrum has been precipitated on hessite (silver telluride), a fineness of 0-8130 
has been recorded by the purchasing banks. 



88 

The bulk of the electrum (" gold ") won from the larger bonanzas of Thames had a fineness 
averaging about 0-6700. It is noticeable that the electrum derived from the Tapu and Tararu 
valleys, where the veins are in proximity to, or not a great distance above, the basement 
sedimentary rocks, is higher in gold than elsewhere — U-740U-0-7500. (The occurrences of 
free " gold " in association with tellurides are here excepted.) 

The electrum occurs in the veinstone either in a fairly fine state of division or in strong 
somewhat jagged shreds, filaments, plates, and granular aggregates. " Gold " showing 
crystalline form, although not uncommon in the neighbouring Coromandel field, has seldom 
or never been reported from Thames. 

Tellurides of Gold and Silver (Hessite and Fetzite). — The occmrences of tellurides in the 
Thames Subdivision are more widespread than have generally been supposed, but not until 
the discovery of lenses of silver telluride containing gold in the more highly minerahsed portion 
of the main reef of the Waitangi Mine have they received much attention. The following 
are the localities at which the presence of tellurium has been detected within the Thames area, 
and to these have been added other known locaUties, as showing the geogxaphical range of 
tellurides in Haurald : — 

Tapu : Quartz containing dense iron and copper pyrites. Assay : 2^ oz. gold per ton, 
250 oz. silver per ton. Analysis showed the presence of 7^ oz. of tellurium per ton — i.e., 
approximately 3 per cent, of the bulhon in the ore (F. B. AUon). 

Waiomo (Gem Mine) : Small sample of white quartz, showing sulphides of silver, but 
no visible gold, along a dark band. Assay : 15 oz. gold per ton, 600 oz. silver per ton ; 12 oz. 
tellurium per ton — equal to 2 per cent, of the bulhon (F. B. Allen). 

Monowai Mine : Ore containing quartz, sulphides of iron, copper, lead, and zinc, with a 
trace of antimony. Assay : 4 oz. gold per ton, 30 oz. silver per ton. Tellurium was present 
in small quantity, amovinting to less than 1 per cent, of the bulhon (F. B. Allen). 

Monowai Mine : Sample similar to above, collected from No. 4 level by the writer. Assay : 
2 oz. 17-9 dwt. gold per ton, 62 oz. 13 dwt. silver per ton. Tellurium was present to the 
extent of 0-03 per cent, of the ore. i , 

Broken Hill Mine : White quartz with blue-black specks, containing iron and copper 
pyrites and sulphides of silver. Assay : 2 oz. gold per ton, 40 oz. silver per ton. The ore 
contained 4 oz. of tellurium per ton (F. B. Allen). 

Tararu Creek : Samples of ore showing copper-pyrites contained a small amount of 
tellurium (F. B. Allen). In 1891 nagyagite was reported as present in rich ore from the 
Sylvia Mine (Park). 

Waitangi Mine (Thames). — Tellurides are here occasionally found in considerable 
quantities in certain streaks and lenses in the reef. The mineral is of a lustrous steel-grey 
colour, and under the lens is seen to be intimately associated with white quartz, the whole 
forming a compact aggregate. An assay of a picked specimen (by Mr. W. H. Baker, Thames 
School of Mines) gave : Gold, 1-3 per cent. ; and silver, 20-6 per cent. An analysis of con- 
centrates obtained by crushing and panning a sample of the high-grade ore (see p. 80) gave 
1-80 per cent, of tellurium. These concentrates, on assay, gave : Gold, 29 oz. 18 dwt. 14 gr. per 
ton ; silver, 932 oz. 3 dwt. 6 gr. per ton. 

May Queen Mine (Thames) : An attractive though small specimen of telluride-ore 
similar to that found in the Waitangi Mine was identified by Mr. W. H. Baker from the 
veinstone of the Queen of Beauty reef at No. 9 (747 ft.) level. 

LocaUties outside the Thames Subdivision : — 

Coromandel (actual position not stated) : Quartz containing 25 per cent, mispickel 
(arsenical pyrites). Assay : 200 oz. gold per ton, 90 oz. silver per ton. This ore contained 
a httle tellurium, the amount of which was not estimated (F. B. Allen). 

Maratoto (Ohinemuri), Silver Queen Mine : A parcel of 106 lb. of ore was reported upon 
by Professor Park, Thames School of Mines, in 1893.* This assayed : Gold, 5 oz. dwt. 20 gr. 

* In 1891 Professor Park recorded the occurrence of tellurium in the ore of the Marototo Mine. He 
also stated that selenium, according to an analysis by W. Climo, was present. See Mines Report, 1891, p. 10. 



39 

per toil ; silver, 270 oz. 19 dwt. 4 gr. per ton. Pau-amalgamation with chemicals yielded 
94-2 per cent, of the gold and 15-4 per cent, of the silver. Laboratory tests showed that the 
greater part of the silver existed as telluride ; the silver recovered by amalgamation was 
probably that alloyed with the gold as electrum. A number of tests with this interesting ore 
showed that from 40 to 50 per cent, of its value was volatilized at a bright-red heat in less 
than two hours. 

Karangahake (Maria Mine) : Specimen forwarded by Mr. J. A. Pond, analysed by Mr. 
W. Skey (1883). Assay: Gold, a trace ; silver, 447-5 oz. per ton. Tellurium was found to be 
present in considerable (juantities. 

Te Aroha (Moa Mine) : Specimen forwarded by Mr. J. A. Pond, analysed by Mr. W. Skey 
(1883). Assay: Gold, 234-25 oz. per ton; silver, 3,928 oz. per ton. Telhirium was found 
to be present in considerable quantities, and was isolated. 

General Statement re the above Occurrences : — 

Hessite (AgoTe), the telluride of silver, is the predominant mineral of this group at Thames, 
and has been definitely identified in specimens from the Waitangi and May Queen mines. 
The frecjuent intimate association of free gold with the tellurides in many of the Hauraki 
samples nnders it doiibtiul in certain cases whether the gold is merely associated or is 
chemically combined w th tilhirium. Hessite often contains gold, and thus graduates 
towards petzite (AgAuoTe). The latter mineral may therefore be present in sjnie of the 
ore. 

Tetradymite (Telluride and Sulphide of Bismuth). — The presence of bismuth in small quan- 
tities in (crtain samples of the telluride-ore of the Waitangi Claim and of the Monovvai 
suggests that tetradymite is present. 

Silver. — The occurrence of silver associated with gold as electrum, the most common 
form, has already been mentioned. Native silver occurs occasionally ; it is said to have 
been seen in the outcrop ore of the We Three Claim, Omahu. 

Argentite (Silver Glance). — Argentite as a fine-grained massive form has been observed 
in bluish-black streaks in the Monowai ore, Waiomo, also in the old Silver Crown Claim (E. H. 
Davis, 1871) and in several other localities. 

Pyrargyrite (Ruby Silver). — This mineral frequently accompanies the gold when the latter 
is found in rich deposits. Its presence was perhaps more conspicuous in the Kuranui-Cale- 
donian Mine than elsewhere. 

Proustite (Light-red Silver-ore).— Proustitc has been recorded l)y Hutton among the 
minerals of Thames. 

Platinum. — Platinum was obtained by Mr. J. A. Pond on analysing vein-quartz from 
between the 540 ft. and 600 ft. levels of the Queen of Beauty Mine, Thames, in amounts 
varying from \\ oz. to 10 oz. per ton. (Mines Rep., 1887, p. 58.) 

Iridium. — The presence of iridium was detected qualitatively in association with the 
platinimi mentioned above (Pond). 

Cinnnbar (Sulphide of Mercury). — This mineral has been mined in the Otanui Valley, 
Kauaeranga, where it occurs in layers of chalcedonic quartz. Specimens obtained from the 
old Crown Princess Mine, Grahamstown, and from water-worn boulders in Hape Creek are 
recorded by Mr. J. A. Pond. It occasionally occurs sparingly in tlie veinstone of other 
localities. 

Pyrite (Bisulphide of Iron). — Pjnite is, next to quartz, the most abimdant mineral in the 
veins of this goldfield. It occurs as cubes and pvritohedrons, and in the massive state. 

Melanteriie (Green Vitriol) is of widespread occurrence, especially in old mine- workings, 
resulting from the decomposition of pyrite. 

Misfich'l (Arsenical Pyrites). — The presence of this mineral is occasionally evidenced in 
several of the mines by the garlic odour following the blow of the pick. Mr. J. A. Pond refers 
to it in connection with veins of Moanataiari Creek and Karaka Creek (Mines Rep., 1887, 
p. 58). 



40 

Native Copper. — The occurrence of fine grains of native copper in dykes which cut 
through breccias in the Thames area is recorded by Cox. The metal has been seen occasion- 
ally in oxidized veinstone at Tinker's Gully and at Waiomo. 

Chalcopyrite (Copper-pyrites). — This mineral is fairly abundant in the veinstone of the 
Sylvia, Waitangi, Monowai, and Mount Zeelian claims, and is occasionally present through- 
out other parts of the field. 

Enargite (Sulphide of Copper, Arsenic, Antimony, &c.) — Attractive specimens of crys- 
tallized enargite have been obtained from a puggy vein following the hanging-wall of the 
main reef at the Magnet Claim, Karaka Creek. It also occurs sparingly in massive form 
in the solid vein-quartz at the same mine. 

Chalcanthitc, or blue vitrol — sulphate of copper — resulting from the decomposition of 
copper-pyrites, in p'aces forms stalactites in old drives. 

Bornite, or Eruhescite (Sulphide of Copper and Iron). — Bornite is found forming an iri 
descent film on chalcopyrite in certain localities. 

Malachite (Green Carbonate of Copper). — Malachite is present as an alteration-product 
wherever chalcopyrite occurs. 

Melaconite (Black Oxide of Copper). — Found as an oxidation-product at Waiomo and 
other localities where chalcopp-ite occurs. 

Cuprite (Red Oxide of Copper). — Occurs sparingly under the same conditions as mela- 
conite. It is mentioned by Hutton in his report of 1867. 

Dioptase (SiUcate of Copper). — Dioptase attached to rock crystal in cavernous quartz 
is reported from the old Wonder Claim (Skey, Rep. 6.S., vi, 1870-71, p. 88). 

Native Lead. — The occurrence of small rounded grains, probably native, in creek-alluvium 
is referred to by Skey (Rep. G.S., vol. vi, p. 86). 

Galena (Sulphide of Lead). — Galena is a fairly common mineral in the veins of the 
country lying between Kuranui Creek and Tapu Creek. It is frequently argentiferous, but 
not highly so. 

Lead-chloride. — Chloride of lead, of straw-yellow colour, is reported to have been obtained 
in considerable quantity at Waiomo (F. B. Allen, Mines Rec, ii, p. 23). 

Native Zinc. — The discovery in the high-level terrace gi-avels of Hape Creek of a boulder 
containing a thin slab of native zinc weighing 4 oz. is recorded (Park, Trans., xxiv, p. 384). 

Sphalerite, or Zinc-blende, is of common occurrence in those veins carrying galena and 
copper-pyrites. It is considered a good indicator for gold in the Kuranui-Caledonian and 
certain other mines where it occurs more sparsely distributed. 

Calamine (Carbonate of Zinc). — A specimen containing calamine deposited on rhodo- 
chrosite (carbonate of manganese) is mentioned by Skey from a claim in the upper part of 
Tararu Creek valley (Rep. G.S., vi, p. 85). 

Genthite (Hydrous Silicate of Nickel and Magnesiimi). — Genthite in a rusty quartz matrix 
was identified from a small vein in a road-cutting about a mile south of Tapu (Park, Trans., 
xxvi, p. 367). 

Arsenopyrite (Arsenical Pyrites). — See " Mispickel " (p. 39). 

Leucopyrite (Arsenide of Iron). — The occasional association of this mineral wnth mispickel 
is mentioned by Cox. 

Stibnite, or Antimonite (Sulphide of Antimony). — Stibnite occurs generally as rhombic 
prisms in spine-Uke or stellate form in vugs in some of the veins. It seems to be more common 
in the veins of Hape Creek than elsewhere. 

Kermesite (Antimony Oxy-sulphide). — This cherry-red coloured mineral resulting from 
the alteration of stibnite is frequently seen coating the parent mineral. 

Cervantite (oxide of antimony) occurs under the same conditions as kermesite. 



41 

Molybdenite (Sulphide of Molybdenum). — Small veinlets of molybdeiiite were found 
associated with a quartz-pjiite vein in the old Kaiser or Iron Cap Claim (now Sylvia Claim), 
Tararu Creek (F. B. Allen, Mines Rec., vol. ii, p. 175). 

Rhodonite and Rhudoehrosite (the Silicate and the Carbonate of Manganese). — These 
minerals are observable in the veinstone of many localities, but are especially characteristic 
of much of the ore of the Day Dawn and Norfolk claims and of the adjoining Watchman 
Claim, imparting to it a delicate amethystene colour. 

Manganite (Hydrous Sesquioxide of Manganese). — Manganite has been recognised in 
the form of small columnar crystals in cavities in quartz from Tararu Creek (Skey, Rep. G.S., 
vol. vi, p. 86). 

Pyrolusite and Wad. — The black oxides of manganese — pyrolusite and wad — are not 
uncommon in certain veins of the subdivision. They are more abundant in some of the 
veins of the Day Dawn and Norfolk Company's claims than elsewhere. The veinstone of the 
upper levels on the City of Dunedin reef was almost black in places owing to the presence of 
these oxides. 

Structure of the Vein-material. 

The form of the veins being dependent on the nature of the fissures will be inferred from 
a previous section. The lenticular form in which the veinstone constantly pinches and makes 
is exhibited in both the larger and the smaller veins formed in fault-fissures. Some of the less 
persistent veins have probably tilled contraction-fissures. A stockwork type of deposit is 
afforded by the reticulated veinlets, or the mineralised sheeted zones. 

The great majority of the Thames veins vary from, say, 2 in. to 4 ft. in width, but stronger 
veins, ranging up to 30 ft. or more, are not uncommon. Both the larger and the .smaller veins 
have afforded pay-ores. 

The vein-material is due, in the main, to the filling of open fi.ssures, but in many cases 
also to the replacement of the wall-rock. In most of the Thames veins — as, for example, 
the Waiotahi-Cambria or the Caledonian — the veinstone may almost be described as massive — 
that is. it shows little or no regular banding or crustification. It is, however, characterize d 
by vuggy and comby structures. The vugs are for the most part small, but occasionally they 
attain fairly large dimensions. Especially do such large vugs occur in the median plane of the 
veins. In all cases these vugs show drusy linings. 

A specimen of the veinstone from one of the small veins — the May Queen specimen leader 
— has been taken for description, as this differs only in dimensions from a great many of the 
veins. This specimen is a tabular mass of 2 in. in width, with fairly smooth well-defined 
walls, to which adhere closely a skin of seamed pyritised propylite. The quartz in the 
vicinity of each wall is massive and compact, except for a few very small isolated vugs, and 
carries in places a little pyrite. On each side of a central druse-lined cavity or fissure are 
very closely packed prismatic crystals of quartz, set with their long axes at right angles to 
the walls of the vein, and these shade imperceptibly into the massive quartz nearer the walls. 
(The comby ijuartz on each side of the drusy cavity in this particular specimen in places 
unites, or again is cemented or lined with secondary minerals — ankerite and barite.) 
The specimen exemplifies the growth of the vein from the fissure- walls, and apparently 
the conversion of the prismatic aggregate of (juartz crystals into the usual compact crystal- 
line veinstone so common on this field. 

Vein-material showing fairly well-marked crustification or banding is observable in places 
in the Sylvia. Waitangi, Watchman, Da}' Dawn and Norfolk. Monowai, and other claims in 
the bedded andesitic flows and breccias lying to the northward of the Town of Thames. 
In the Sylvia and Waitangi mines especially, where zinc-blende, copper-pyrites, and galena 
occur with the quartz gangue, the banded structure is particularly evident. 



42 

Sacchaioidal, or " sugary " quartz, which may be due to the crushiuy accompaiiymg 
rock-movement, and also a peculiar cellular white quartz exhibiting the appearance of having 
been leached, occur in places in the large vein of the Watchman Mine. 

The platy or laminated structures and the hollow rhombohedral cavities — quartz replace- 
ments after calcite — which are so common at Waihi, Kuaotunu. and elsewhere, are rarely 
seen in the Thames veins. 

That certain veins represent in great pait wall-rock silicified and otherwise mineralised 
is apparent. The circulation-channels in such cases were evidently in jilaces fracture zones, 
and not open fissures. Brecciation is frequently noticeable. Parallel ribs of quartz and reti- 
culated veinlets of quartz intersect these mineralised zones or bands. The surface stockworks 
of Kuranui Hill and Shotover Gully and of Una Hill, with their somewhat indefinite and 
irregular boundaries, are related to this class of deposit. 

Minor variations in the structure of the vein-material will be noticed in connection with 
the detailed description of individual veins. 

Oxidation. 

The depths to wliich oxidation has afiected the upper portions of the veins is exceed- 
ingly variable. In addition to the original ground-water level, which is not now ascertainable, 
the porosity of the veinstones and of the enclosing rock and the presence or absence of fissures 
and fractures appear to have been potent factors in governing the vertical extent of the oxida- 
tion zone. 

The most obvious effect of oxidation on the vein-material is the conversion of p}Tite 
into the rusty- coloured limonite. T}'pical hard, rusty, cemented gossans, or " iron caps," 
are few — perhaps that of the old Iron Cap Claim (part of Syh-ia) is the best example. 

The manganese-carbonates particularly common in the Tararu Creek area are changed into 
the black sooty oxides. In the veins containing copper-pj-rites the carbonates — malachite 
and occasionally azurite — and the varicoloured oxides are conspicuous. 

In the oxidized ores gold (electrum), originally associated with sulphides, is liberated, 
but the ratios of the alloyed metals — gold and silver- -differ little from those obtaining in the 
electrum of the anoxidized portions of the veins. 

The Ore-deposits. 

The payable ores in the auriferous veins are generally disposed as shoots or patches — 
tabular masses of more or less definite outUne. From the rather incomplete records relating to 
the notable ore-shoots discovered in the area, the descriptions and sketches embodied in the 
detailed account of the various mining claims have been compiled. 

The pitch-lengths of these bonanza shoots have generally exceeded tht stop e-lengths, and 
the shoots have nearly always been disposed almost vertically within the plane of the veins. 
Where, however, a bonanza has been genetically connected with a fault-fissure striking more 
or less transverse to the vein the shoot has followed the dip of the fault. The majority of these 
faults pitch westward (seaward). 

The factors which have exerted the greatest influence on the locaUsation of the ore-deposits 
are : (a.) The character of the country rock ; related to this is the existence of productive 
zones, (b.) The nature and disposition of the vein fissures and the existence of intersecting 
veins, flinties, pyritic veinlets, faults, and cross-courses, (c.) Depth. 

(a.) The Character of the Country Rock and the Existence of Productive Zones. — The ex- 
perience of the past forty years has led the miner to distinguish between rock favourable 
for the existence of gold in the quai-tz veins and rock which is unfavourable. 

The favourable rock, or, to use the miners' term, the " kindly sandstone," is a completely 
propylitised flow andesite, light-grey in colour, fairly uniform in texture, moderately hard, 
and containing disseminated fine grained pyrite havmg a splendent lustre — " bright mineral." 



43 

In the harder and darker andesite into which the propyhte grades, the veins invariably 
become smaller and poorer, and often " pinch out " to mere clay-filled seams. The greenish 
chloritised andesite, which in places marks a gradual transition from propylite to unaltered 
andesite, is almost invariably barren. 

Veins intersecting the altered tuffs and breccias, the " mottled country " of the miner, 
have with few exceptions proved either poorly productive or barren, and are, furthermore, 
not so well defined as those in the altered flow andesites. This has so far proved quite a cha- 
racteristic of the Thames field. At Karangahake, however, some twenty miles farther south, 
very high-grade ore is being mined from the Talisman reef, at No. 13 level, where it intersects 
propyhtised well-consoUdated andesitic breccias. There is thus no certainty as to the conditions 
which may obtain in the consoUdated breccia country at the deeper levels of Thames. 

At Thames, as in other mining centres of Hauraki. certain fairly definite productive and 
non-productive zones of comitry are recognisable. The existence of such zones is to some 
extent dependent upon the character of the country rock, but they also appear dependent 
upon some other factor not easily explainable. 

The principal productive zone at Thames is that in the Central Block, extending in a 
general south-easterly direction from Shotover Creek and Kuranui Hill to the Queen of Beauty 
Claim. As it is approximately transverse to the various parallel veins which have within its 
hmits proved so productive, the occurrence termed in mining " ore to ore " or shoots " back 
to back " is here well exemplified. 

In the Upland Block a productive zone followed the Moanataiari " cross-lode " on its 
intersection of the Reuben Parr, Golden Age, and other reefs. Again, the Dixon's, the 
Sons of Freedom, the Success, and other veins in the Old Alburnia Claim, and the Duke's 
and the Pride of Karaka veins in Una Hill also carried their main ore-shoots " back to 
back." 

The main Kuranui - Queen of Beauty zone is disposed with a pronoimced dip to the south- 
south-westward (see J lans and sections). In the northern end of the area it outcrops at the 
surface ; further southward it is overlain by much less-productive country. These conditions 
render it doubtful to what extent the bonanzas of Thames are due to a long-continued 
superficial secondary enrichment of leaner ores, or are the product of original concentrations 
perhaps again and again enriched. The theory that the precipitation of metals takes place at 
" critical levels " mider varying conditions of temperature and pressure receives support from 
the existence of the fairly definite floors which carry the pay-ores on this and other of the 
Hauraki goldfields. 

(b.) The Nature and Disposition of the Vein Fissures and the Existence of intersecting Veins, 
" Flinties," Pyritic Veinlets, Faults, and Cross-courses. — All the great bonanza shoots of the 
field, with the exception of the Prince Imperial, occurred at points of marked local enlarge- 
ment of the enclosing veins ; the veins, moreover, in these localities showed considerable 
contortions in strike and dip, and are evidently connected with very complex systems of 
rock-fracture. Cox has observed that within a productive zone the " mean underlie of the 
reefs has not in any way affected the distribution of the gold. . . . When, however, 
we come to consider the successive inclinations of the individual reefs we find that (excepting 
in one locaHty — Alburnia) wherever notice has been taken the steepest parts proved the 
richest."* 

The detailed descriptions of the various bonanza deposits are indicative of the very im- 
portant part vhir-h intersecting veins have played in the localisation of the rich ores of this 
field. At such intersections the mingling of waters that have come from different sources or, 
travelhng via different directions, have acquired different characters, has resulted in the 
precipitation of the gold and its associated minerals. 



* Rep. G.8. during 1882, vol. xv, 1883, pp. 43, 44. 



44 



(1-) 

. . 55-30 


(2.) 
^5-25 


5-76 


3-25 


3-52 


4-32 


7-45 


MO 


2-90 


1-20 


. . 0-62 


0-32 


0-28 


0-17 


Nil 


Nil 


. . 12-90 


9-27 


9-76 


3-94 


1-51 


1-18 



A special type of intersecting veins are the " flinties." These veins, which, as the name 
implies, have rather a flinty appearance, are themselves barren or practically barren in the 
precious metals, but have usually had such a pronounced effect in the precipitation of gold in 
the reefs at their intersections that they have come to be regarded as " indicator " veins. It 
has been noticed that the presence of a thin seam of pug or of a film of quartz between the 
intersection of the " flinty " and the veinstone is sufficient to cause the gold-content of the 
latter to fall to zero, while where uninterrupted contact takes place ore of bonanza richness 
is hkely to be found. Analyses of representative samples from two of these flinties — 
(No. 1), from the May Queen Claim ; (No. 2), from the New Occidental Claim — are as 
follows : — 

Silica (SiOa) . . 
Alumina (AI2O3) 
Ferric oxide (FejOj) 
Lime (CaO) . . 
Magnesia (MgO) 
Potash (K2O) . . 
Soda (Na^O) . . 
Titanium-dioxide (TiO.j) 
Iron-pyrites (FeSj) 
Carbonic anhydride (CO 2) 
Undetermined 

100-00 100-00 

(1.) Gold per ton, 15 gr. ; silver per ton, 15 gr. ; 
(2.) Gold per ton, 7 gr. ; silver, nil. 

The small pyritic veinlets have a similar but more local effect. The wall-rock in the 
actual vicinity of rich bonanza ore is frequently observed to be seamed with a network of 
thread-like pyritic veinlets. As mentioned later in the description of the Waiotahi Claim, the 
pyritic veinlets in a certain locality were auriferous, and were present in such abundance as 
to render the country rock payable to mine. 

The common association of faults and cross-courses with the localisation of the very rich 
ore is a particularly noticeable feature. Many of these intersecting and dislocating fissures 
evidently originated prior to advanced concentration of the gold and silver in the rich vein- 
stone, although the formation of the vein fissures that exhibit offsets must be regarded as 
antedating the faulting-movements along the dislocating fissures. The theory has been 
advanced in subsequent pages that the Moanataiari fault has had considerable effect on the 
localisation of the richer ores of Thames other than that attributable to mere protection from 
erosion of a particular zone of country by downthrow. As evidence of the formation of a 
quartz vein, subsequent even to the last great movement along this fault-plane, it is stated 
that in the Kuranui Claim a small but well-defined vein striking transversely to the fault 
was found to persist right through the clay-filling of the fault. 

In the great majority of cases which have come under the writer's notice, both at Thames 
and in the neighbouring Coromandel field, the rich bonanza ores occurred in the veins on or near 
the hanging-wall rather than the foot-wall side of the faults. This would appear to indicate 
that, locally, at any rate, the minerahsing solutions effecting the ore-concentrations were 
descending. 

Faults and cross-courses may have influenced precipitation in the vein-channels by sup- 
plying precipitating-solutions, but in many cases they appear to have oft'ered almost impene- 
trable barriers to migrating solutions, and to have thus determined separate local systems 
of circulating ground-waters. 



46 

(d.) Depth. — The results of mining explorations of the past forces one to the conclusion 
that 500 ft. has proved a critical depth on this field. Irrespective of the elevation of the vein- 
outcrops, little payable ore has been mined from a depth exceeding 500 ft. below the existing 
surface. The downward limit of the pay-ores mined appears, therefore, to conform roughly 
to surface-contours. 

The question which is inevitably the first to be raised, and which has been aptly put 
in a report on an analogous field — Cripple Creek, Colorado — is, " How far does the distribu- 
tion of known pay-shoots represent the distribution of all the pay-shoots in the district ? " * 
In other words, how far has exploration been impartial in revealing ore-bodies near the surface 
and at depths greater than 500 ft. ? At the Thames the rocks from the surface to a depth 
of 500 ft. have been riddled with adits, shafts, drifts, and crosscuts, while the deeper horizons 
have been explored by few mine-workings other than the main " 640 ft. " crosscut, and the 
extension of the Moanataiari tunnel. It is obvious, then, that the chances of ore being dis- 
covered near the surface have been very much greater than the chances of ores being 
discovered at greater depths. The results of the deep - level development scheme just 
initiated will, however, afford a safer basis for generaUsation. 

Mining exploration may be considered to have revealed the fact that a great many of the 
veins worked in the shallower levels are " hanging-wall droppers " of certain of the larger flatter- 
lying reefs. It has been shown that the ore-bodies have been intimately connected with 
fissures, and it appears certain that Assuring has been much more pronounced nearer the 
surface than at greater depths. This feature, then, implies a smaller development of ore-shoots 
as greater depth is attained. The predominance of pay-ores in the shallower zone, due to the 
increased fissuring of the rocks in this zone, rather discounts the importance of secondary 
enrichment attendant upon a gradual downward migration of the belt of weathering. 

That ore-shoots in metalliferous mines decrease in number as greater depth is attained 
is regarded by some authorities as a proven fact. This feature is believed to be connected 
with the fundamental laws governing the solution and the precipitation of metals under varying 
conditions of temperature and pressure. 

As to how much of the land-surface has been planed off at Thames by the agencies of 
erosion since the ore-bearing veins were formed, it is impossible to estimate. It certainly 
runs into hundreds of feet, and it is likely that this vanished zone of rock contained numerous 
reefs and many ore-shoots. Unfortunately, most of this auriferous rock-waste was discharged 
by the streams on to an old foreshore now depressed hundreds of feet below sea-level, and 
overlain by recent alluvium. A little gold and " specimen stone " was, however, in the earlier 
years of mining obtained from creek gravels strewn over this harbour alluvium. 

It would appear that at Thames the vein-forming solutions ascended fairly rapidly 
through a comparatively few persistent and very deep fissures, and that they were distributed 
from these to the branching and complicated rock-fractures of shallower horizons, diminishing 
their velocity and gradually changing their composition. This would imply that, on the 
whole, the deeper ground can hardly be expected to prove as highly productive as the shal- 
lower zone. Furthermore, such conditions, as pointed out in connection with Cripple Creek, 
" would help to explain the frequent precipitation by mingling waters at the intersection 
of fissure8."t 

Underground Temper.\tures. 

Some observations were made during the course of the present survey in certain of the 

Thames mines with a view to determining the increment of temperature with depth. Although 

every precaution was taken in selecting the points at which the temperature of the rock was to 

be taken, the results were rather disappointing, and many of the measurements had to be 

• Lindgreni W., and Ransome, F. L. : "Geology and Gold Deposits of the CiippIe Creek District, 
Colorado." Prof. Pajn;", U.S. Geol. Sur., No 54, 1006, p. 214. 
t Loc. cit., 11. 216. 



46 



rejected as obviously misleading. The heat generated by the chemical action attending the 
oxidation of the rock due to slowly percolating waters was the main difficulty ; while in other 
cases it was not easy to avoid some influence due to the ventilating air-currents. WTiere 
observations were to be taken, holes were drilled dry 24 in. into the rock, and stopped up with 
plugs, the actual measurements not being made until the heat due to drilhng had been given 
off. The thermometer was allowed to remain in each stopped hole over twenty minutes before 
taking the reading. The results of temperature-observations are as follows : — 



Temperature. 



Depth required for Increase 
of 1° Fahr. 



Feet below Surface. 


Moanataiari 
Tunnel.- 


1 
May Queen 
and Queen 
of Beauty. 


■i .2 


1 

Waiotahi. | 


May Queen 
and Queen 
of Beauty. 


Kuranui- 
Caledonian 


IS 

o 

■3 


< 




Deg. Fahr. 


Deg. Fahr. 


Deg. 
Fahr. 


Deg. 
F...hr. 


Ft. 


Ft. 


Ft. 


Ft. 


50 


58-8* 


58-8 ' 


58-8 


58-8 


, . 




. , 


• • 


352 (No. 3 level, Kuranui- 






64-5 


, , 




52-0 


, , 




Caledonian) 


















■128 (No. 6 level, Waiotahi) 




. . 


. . 


70-8 




. . 


31 15 




467 (No. 4 level, Kuranui- 






67-1 


. . 


, . 


44-2 


. , 




Caledonian) 


















518 (No. 4 level, May Queen) 




70-50 


. . 


, , 


40-0 




, . 




518 (No. 7 level, Queen of 




71-00 




, , 


, . 




, , 




Beauty) 












. 






626 (No. 5 level, May Queen) 




72-75 




, , 


45-3 


• ■ 


, , 




825 (No. 9 level, May Queen) 




77-50 


. . 


, , 


41-9 




. . 




1,000 (Queen of Beauty) . . 




81° air, 91° 
water, 
(say 83°) 






31-8 








970 (beyond bottom of Al- 


73i 






. . 


. . 


. . 




62 


burnia rise in Moana- 
















taiari tunnel, before 
















connection was made 


















with upper levels) 






: 











* Say annual mean temperature. 
Mean average, 1° Fahr. in 43-5 ft. 
The measurements obtained, although they can only be regarded as approximate, indi- 
cate that the rate of increment of temperature with depth, at least in the mines on the hanging- 
wall side of the Moanataiari fault, is high. The average increase is probably about 1° Fahr. for 
each 43 ft. of vertical descent down to 800 ft. The single observation available at a depth 
below 800 ft. from the surface in thes;-» mines suggests a considerably higher rate of increment 
for the deeper levels. The following comparisons are interesting ; — 



Temperature. 
78° Fahr . 

73-5° Fahr. 



Tonopah, U.S.A. 
(Ohio Shaft). 

766 ft. 
(Mispah Extension) 

780 ft. 



Comstock, U.S.A. 

(F Shaft). 
900 ft. 



Thame? (May Queen 

and Queen of Beautv). 

850 ft. 

600-700 ft. 



600-700 ft. 

At Comstock the average increment of temperature is 1° Fahr. for each 33 ft. in vertical 
descent, and it is not unlikely that at Thames the increment may be almost as high as this 
at and below 1,000 ft. from the surface. 



47 



Underground Gases. 

The presence of mine-gas in certain of the Thames mines, especially those located on the 
seaward (downthrow) side of the Moanataiari fault, is not only a source of considerable annoy- 
ance to workers, but has at times caused suspension of mining operations, and has been attended 
with loss of life. Even within a comparatively limited radius certain mines may be more 
troubled with gas than others. Generally speaking, the deeper the mine-workings the more 
abundant is the amount of gas present. 

The following analysis was made of gas collected from a winze in the Saxon Claim, and 
it may be taken as fairly representative : Oxygen, 8-2 per cent. ; nitrogen, 54-6 per cent. ; 
carbon-dioxide, 37-2 per cent. — total, 100. The specific gravity relative to air is 1-19. The 
mine-gas is therefore equivalent to a mixture of 39-2 volumes of air, 37-2 volumes of nitrogen, 
and 23-6 volumes of carbon-dioxide. If the air be regarded as an accidental admixture 
the pure gas would consist of 61-2 per cent, of nitrogen and 38-8 per cent, of carbon- 
dioxide.* 

The gi',s is colourless, and when encountered in the mine appears to have a faint sm(;ll, 
leaves a sUghtly acid taste in the mouth, and causes a peculiar miM prickly sensation on the 
skin. It produces, of course, the usual effects of suffocation. 

The gas usually emanates from fissures in the country rock and in the quartz veiivs, 
sometimes witli such velocity as to produce a whjsthng sound. It may, however, issue uni- 
formly from the country rock where the latter is of a particularly porous character. 

Owing to its relatively high specific gravity it tends to lodge in the lowest parts of the 
mine-workings — on the floors of the drives, in the winzes, &c. Where not disturbed the 
top of the substratum of gas appears to be fairly sharply marked off from the ordinary air, 
a Ughted candle being suddenly extinguished at a definite horizon. Influx of gas takes place 
during periods of low barometric pressure, and, conversely, the mine-air is generally good 
when the barometer is high. At Thames the northerly and easterly winds — the rain-bearing 
winds — to some extent detrimentally affect mine-ventilation, and are attended with increased 
exhalations of gas. The occasional pecuUar movements of volumes of gas, however, suggest 
that some other factor in addition to variation of atmospheric pressure has an influence. 

Although no definite measurements have been made, it is fairly safe to assume that at 
any particular horizon the gas is at a higher temperature than ihe ordinary mine-air. " Gassy " 
mines on this field have always the reputation of being hot. 

The gas occurring in great quantities in the mines at Thames cannot be ascribed to local 
chemical action of any kind, and is, in the writer's opinion, nragmatic — the dying exhalations 
of an extinct volcano. 

The question of effectively combating the gas difficulty in certain of the Thames mines 
is not an easy one, and, judging by the conditions at the " 640 ft." crosscut, the ventilation 
of the workings at the 1,000 ft. level will require very careful consideration. " At the Moose 
Mine (Cripple Creek, Colorado) strong blowers were used with indifferent effect ; experiments 
were made both by exhausting the gas and by forcing in fresh air. At times of low atmospheric 
pressure all measures fail at this and other mines, as the gas pours out in irresistible volumes. 
The very next day the mine may be free from it."* 

The following suggestions made in the report on Cripple Creek are equally applicable to 
Thames : " It would seem that the only really effective way of combating the evil would be 
to maintain in emergencies, by means of powerful blowers and properly arranged air-curtains, 
a pressure in the workings which would slightly exceed the normal atmospheric pressure. 
This is called the ' plenum ' system of ventilation, and has been successfully apphed in coal-mines 



* An estimation of the composition of the pure eas in the Elkton Mine. Chippie Creek, gp,ve 80 per cent, 
nitrogen and argon, and 20 per cent, of carbon-dioxide. (Lindgren and Rantiome, loc. cit., p. 255.) 



48 

and ill tlie alluvial mines of \'ictoria, the olijectionahlc gas being carbon-dioxide in the latter 
case. At least this method could be applied to certain parts of the workings. Considerable 
expense and some difficulties would no doubt be connected with it. In case of failure of the 
blowers it would no doubt also increase the danger to the men woiking in the mine, but in 
some cases it would seem to be the only possible remedy."* 

It should be stated that no attempt has been made at Thames to systematically record the 
atmospheric and other conditions which have attended the movements of mine-gas in the 
workings or certain parts of the workings in the foreshore claims. In view of the contem- 
plated deep-level exploitation it is highly desirable that regular and careful observations 
be now instituted and the results tabulated. Such .specific data will be foimd of the greatest 
value when the problem of deciding upon the most effective method of ventilating the deeper 
workings presents itself. 

Underground Water. 

The original ground-water level at Thames camiot now be ascertained, owing to the 
existence of numerous drainage-adits and also to the maintenance of an artificial water-level 
due to pumping operations. 

Doubtless the original water-level on the flat at Thames stood at about sea-level, and 
further back it rose fairly rapidly, following somewhat more modified contours than those 
of the hilly land-surface. 

The Moanataiari tunnel, with its numerous offset drifts, extending back from the sea- 
border for over a mile, affords a fairly heavy constant stream of water of rather rusty colour ; 
so also do certain minor adits driven from the several creek valleys.f 

The claims on the seaward side of the Moanataiari fault are drained to a general level 
of about 430 ft. below sea-level, excepting the area in the more immediate vicinity of the 
Thames-Hauraki pump shaft, where the level descends to a maximum of 1,000 ft. The amount 
of water raised j)er diem is about 1,120,000| gallons, or in a year is equal to the capacity of a 
reservoir 28-9 in. deep covering about 623 acres, the latter being the area assessed by the 
Drainage Board as deriving benefit from the pumping-operations. The mean rainfall, it may 
be remarked, is approximately 48-6 in. per annum. 

The Moanataiari fault, which hmits the " central " block to the eastward, has been cut 
at two points in the " 640 ft." level, also in May Queen No. 5 level, and elsewhere, so that a 
certain amount of drainage from the upland block finds its way to the pump shaft. Owing 
to the relatively impervious nature of the sUckensided clays associated with the Beach 
" sUde," and of the silts of the Firth of Thames flanking the steep submerged landscarp 
determined by this " slide," it is unlikely that any appreciable amount of water enters the 
drainage-area from the westward. 

The underground water is, in the main, confined to the veins, open fissures, cross-courses, 
faults, and shattered zones of rock. Drifts in the altered or unaltered andesite are 
relatively free from water until such structural breaks are encountered. 

The temperature of the water raised at the pumping-station is somewhat above the normal 
sirrface-temperature, and is more or less discoloured by oxides of iron, and has a sUghtly 

*Lindgren and Ransome :" Geology and Gold Deposits of the Cripple Creek District," Prof. Paper, 
U.S. Geol. Suivey. No. 54, 1906, p. 258. 

t According to Mr. Joseph Brokenshire, as quoted by P. G. Morgan (Eng. and Min. Journal of New 
York, 15th September, 1904, p. 429), the flow of water from the Moanataiari adit was at that time almost 
exactly 30 cubic feet per minute. From the other adits of the field probably not more than another 30 cubic 
feet per minute was then flowing. 

t In 1903 the water pumped by the old Big Pump is stated (see last reference), to have been 675 
gallons per minute, or 972,000 gallons per diem. 



49 



astringent taste. It deposits an incrustation in the pump-launders, &c. 
deposit from the old Big Pump station is as under * : — 

Carbonate of Lime . . 

Carbonate of magnesia 

Iron-oxides with alumina 

Siliceous matters, insoluble in weak acid 

Soluble sihca 

Water 

AlkaUes, sulphur, &c. 



An analysis of such 

85-94 
0-84 
6-69 
2-18 
044 
217 
1-74 



100-00 



An analysis of water from a fissure at the 1,000 ft. level, Thames-Hauraki shaft, taken at 
temperature of 92° Fahr., is as under (the results are expressed in gi'ains per gallon) : — 



Mineral Water. 



Slhca (SiOj) 

Alumina (AljOg) . . 

Ferrous oxide (FeO) 

Lime (CaO) 

Magnesia (MgO) 

Potash (KaO) 

Soda (Na^O) 

Bar>-ta (BaO) 

Carbonic anhydride (COj) 

Sulphuric anhydride (SOg) 

Chlorine (CI) 

Iodine 



Less oxygen equivalent to chlorine 



4-50 

2-50 

0-14 

3800 

1700 

Nil. 

86-10 

Trace. 

84-40 

58-60 

6110 

Nil. 

352-34 

i:v80 



Total solids 
These results may be recalculated as follows 

Sodium-silicate (Na20.4Si02) 
Sodium-chloride (NaCl) 
Sodium-sulphate (NajSO^) 
Aluminium-sulphate (Al2(SO^)3) 
Magnesium-sulphate (MgSO^) 
Magnesium-bicarbonate (MgH2(C03)j) 
Calcium-bicarbonate (CaH2(C()3)2) 
Ferrous bicarbonate (FcH2(C03)2) 



3 58-54 

Grains 

per Gallon. 

5-4 

100-7 

72-9 

8-4 

17-4 

40-9 

109-9 

0-3 



355-9t 



* Notes on tho Deposit in the Shaft of the Pumping Association (Thames), G. Black, Trans, vol. x, pp. 456, 
to 458. 

t Included in this total i* a weight of 17-3 gr. H2O combined as bicarbonate, which doss not appear in 
the first list. 



4— Thames. 



50 



CHAPTER VI. 



DETAILED DESCRIPTIONS OF MINING AREAS AND MINING CLAIMS. 



Manaia Valley 
Waikawau Valley . . 

Te Mata Valley . . 
Tapu Valley 

The Sheridan and Adjoining Claims 

Mclsaac's Old Claim 

Mahara Royal Area 
Diehard, Whalebone, and Oturuturu VaUeys 
Puhoi Valley 

Mount Zeehan Claim 
Waiomo Valley . . 

Monowai Claim 

Colorado (Old Comstock) Claim . . 

Paroquet Claim 

Golden Gem Claim 
Puru Valley 

Puru Consolidated Claim 

Puru Big Reefs Claim . . 
Otohi Valley 
Tararu Valley (above Ohio Creek Junction) . 

EcUpse Claim . . 

Scandinavian Claim 

Chicago Claim . . 

Temple Bar Claim 

Argosy Claim . . 
Kaimarama Valley 
Waiwawa and Ounaroa Valleys 
Kauaeranga Valley 

Otanui Consols Claim . . 

The Cinnabar Occurrences of Mangakiri 
kiri 
Kirikiri Valley . . 
Wharehoe and Matatoki VaUeys 
Puriri Valley 
Omahu Valley 

The Mining-area and Mining Claims at and 
near the Town of Thames (Thames Special 
Area) 

Boundaries of the Special Area . . 

The Oldest Rocks 

The Vein-bearing Rocks 

(a.) The Andesitic Flow and Breccia Com 
plex . . 



Page 
50 
51 
51 
52 
52 
53 
64 
54 
55 
55 
56 
56 
59 
59 
60 
60 
60 
61 
61 
61 
61 
62 
63 
63 
63 
63 
64 
64 
65 

65 
66 
66 
66 
67 



67 
67 
68 



68 



The Mining-area and Mining Claims at and 

near the Town of Thames (Thames Special 

Area) — continued. 
The Vein-bearing Rocks — continued. 

(h.) Non-brecciated Andesite (the " Pre- 
mier " Flow) . . 
Structural Breaks 
The Gold-bearing Reefs 
Day Dawn and Norfolk Claim 
Watchman Claim 
Dixon's Consolidated Claim 
Sylvia Claim . . 
Bonanza Claim 
Waitangi Claim 
Old Albumia Claim 
Moanataiari Extended Claim (Hidden Trea 

sure) 
Reliance Claim 
Thames Claim . . 
West Coast Claim 
Golden Drop Claim 
Magnet Claim . . 
Arrindell Claim 
Halcyon Claim 
Southern Queen Claim . . 
The Mining Claims of Una Hill and Vicinity 

Lone Hand Section of May Queen Claim 

May Queen Extended Claim 

New Una Claim 

New Occidental Claim 

New Dart Claim 

Anchor or Ethel Reefs Area 

Other Claims 
Kuranui Claim 
Kuranui-Caledonian Claim 
New Moanataiari Claim . . 
Waiotahi Claim 
Victoria Claim . . 
Saxon Claim . . 
May Queen Claim 
Shortland Flat Claim 
Vanguard Claim 
Thames Deep-levels Consolidated Claim 



Page 



70 
70 
71 

74 
75 

75 
77 
78 
81 

85 

85 

85 

87 

87 

87 

88 

89 

90 

90 

92 

92 

92 

93 

93 

94 

95 

95 

96 

99 

103 

106 

108 

110 

114 

115 

115 



only 



Manaia Valley.* 
the southern portion 



of the watershed falls within the 



In the Manaia Valley, 
Thames Subdivision. 

The veins occur in the stratified rocks of the Tokatea Hill Series and in the propyhtised 
andesites which here overlie them. Many of the " felsitic " stratified rocks at Manaia, with 
which are associated numerous intrusives, bear a striking resemblance to those which constitute 
the greater part of the country rock of the Royal Oak and neighbouring mines of Tokatea 
Hill at Coromandel. Nevertheless, the total gold-output of Manaia has been small, and no 
mining operations are at present in progress. 



* Manaia Valley. For notes on northern portion, see p. 129, Bulletin No. 4. 



61 

The old Golden Hill or Victoria Claim, near the snmll Paekihauraki Creek, afforded a 
limited amount of rich " specimen stone " to the prospectors — Blackmore and party ; but 
subsequent operations by one or two small mining companies were unsuccessful. As further 
development would entail the cost of shaft-sinking and pumping, this claim, which still is 
considered a promising one by some of the miners who were connected with it, has been 
abandoned. The mine-workings consist of three adit levels, all in a state of collapse. 
The country rock is a much-jointed dark shaly argillite, and the veinstone of the old dumps 
appears to have been derived from small reefs and brecciated bands. The rich ore is said to 
have been confined to isolated patches or pockets. 

The stretch of country drained by the main branches of the Manaia, and extending back 

near to the sources of the Waikawau, carry quartz veins, but although the creek-gravels bear 

in places " colours " of gold, no promising prospect has yet been located. It cannot be affirmed 

. that the Manaia Valley has been systematically prospected, and there appears to be no reason 

why further discoveries should not be made. 

Waikawau Valley. 

Southward of Manaia Valley the country Iving between the western coast-line and the 
crest of the main range affords no mineral indications until the upper valley of the Waikawau 
is reached. Here detrital gold is obtainable throughout a small stretch of country extending 
from McLaughlin's Freehold to Hunt's Creek, on the north side of the valley. 

Near the northern bank of the Waikawau, on McLaughlin's Freehold, the hanging-wall 
portion of a vein or mineralised zone of unascertained dimensions is exposed. A general 
sample of the available material, which was highly pyritised, yielded on assay : Gold, 4 dwt. 
10 gr. per ton ; silver, 2 oz. 13 dwt. 12 gr. per ton — value, £1 3s. Further prospecting on 
the vein is advisable, considering that along its supposed northerly strike very finely divided 
gold is obtainable from the hillside debris as far as the headwaters of Whakarewa Creek. 

In Hunt's Creek, which incises andesitic rocks exhibiting various stages of alteration, 
the marks of the prospector of the early days are noticeable. Prospects of gold obtained 
from the creek debris led to exploration of the valley, without, however, payable results. 
The finding of loose pieces of " specimen stone " was reported. Compact vein-quartz is 
here rarely encountered, and mineralisation seems to have been mainly confined to silicifi- 
cation of the andesites along certain narrow zones of fracture with the introduction of pyrite 
and to a less extent of stibnite. The highest assay obtained for gold-silver (5s. lOd. per ton) 
was afforded by a 10 ft. vein-formation crossing the creek at the waterfall about half a mile 
from the jmiction with the main Waikawau Stream. 

Te Mata Valley. 
In Te Mata Valley one or two small streamlets entering on the south side and incising 
the Jurassic grits and argillites carry a few fine '• colours" of gold, but the main auriferous 
area is confined to the propylitised andesite belt of Gentle Annie Creek and its vicinity. This 
creek, which was in the early days sluiced almost to its head, afforded a considerable amount 
of detrital " specimen quartz " and gold, but all efforts to discover a payable quartz vein 
have proved futile. Since 1887 the official records show a total of only 191 oz. of gold-silver 
buUion as the output of this area. Most of this appears to have been derived from the hill 
which rises from Te Mata Stream immediately eastward of the Gentle Annie Creek junction. 
The mullock-dumps of several small drives are here noticeable, and those drives which are still 
open show small non-persistent rubbly quartz veins. That such was the character of the 
veins which afforded the material crushed is indicated by the reports. A small crushing 
and amalgamating plant was in 1888 erected at the foot of this hill, and 61 tons of ore crushed 
from the old Gentle Annie and Mata claims returned 62 oz. of gold-silver bullion. In the 
following year 164 tons were crushed for 64 oz., and the area was abandoned. 

4*— Thames. 



52 

A large well-defined reel in the Gentle Annie Valley, striking about noith-south and 
carrying rather flinty quartz, is traceable for a distance of at least 25 chains. Assays of general 
samples from various parts of this reef showed a gold-content ranging only from 1 gr. to 8 gr. 
per ton, and silver from 1 dwt. 5 gr. to 1 dwt. 21 gr. per ton. Other small veins occur carrying, 
where exposed, equally low values, and the small pockets of rich ore mined fi'om certain of 
these was confined to small seams and stringers. Whether the erosion of the upper horizon 
of those veins already located or of veins concealed beneath the heavy overburden of hillside 
debris afforded the alluvial gold it is impossible to determine. The fact that no samples of the 
" specimen " quartz won from the early sluicing operations could be obtained for comparison 
with the quartz of the veins exposed rendered the problem even more difficult. 

The whole of the upper Mata Valley from a point half a mile above the jvmction of Gentle 
Annie Creek is barren of metalliferous veins for the reason that the andesites visible in this 
locality are referable to the Beeson's Island Series. 

Tapu Valley. 

The valley of Tapu Stream, although at present commanding little attention from a 
mining point of view, yielded in the past a considerable amount of gold, partly from reefs 
and partly from the sluicing of hillside talus and stream gravels. Hutton, in his report of 
1869, records the existence of more than a hundred mining claims and a population of about 
five hundred people. The total gold-silver output up to the end of 1885 is stated to have 
been 35,000 oz., and from 1887 to the end of 1908, 8,520 oz. The value of the metal exported 
from the valley could on these figures be assessed at over £130,000. 

The auriferous veins which have proved most remunerative occur in the lower portion 
of the valley, both in the stratified rocks of the Tokatea Hill Series and in the overlying pro- 
pylitised andesites of the " First Period." The auriferous belt here appears to be genetically 
connected with a main line of faulting. The fault or " main slide " strikes south-east from 
Mclsaac's claim in the No. 3 gully, and has been located in the old Golden Point, Sheridan, 
and Bullion claims, on the south side of the main valley. Another fault strilcing south-west 
from this one towards the coast-line is stated to have been located in the mine- workings, and 
is mentioned by Hutton (1869) as terminating at the surface the southern extension of the 
slaty basement rocks. 

As all the principal underground workings are now inaccessible, it is impossible to offer 
more than general remarks concerning the area. The veins, which were all of the bonanza 
type, varied in width from a fraction of an inch to 4 ft. All the mining was carried out from 
adit levels, except in the case of the Golden Point Company's claim, where a httle work was 
done from a shaft sunk near the bed of the main stream. Probably the Sheridan and Mclsaac's 
claims have proved the most productive, and in each case the veins occurred in the vicinity 
of the main fault. 

The Sheridan and Adjoining Claims. — A plan of the lower Tapu auriferous area, which 
shows the locality of the bonanza of the Sheridan Claim made from information gleaned from 
the prospector is submitted with this report. (See Fig. p. 53.) 

The country rock of the Sheridan reef is a propyhtised fine-grained w^ell-consolidated 
andesite breccia. The ore obtained within the limits of the bonanza on this and the cross- 
reef was very rich, some of the " specimens " returning 3 oz. of gold to the pound of stone. 
The records of the output from this patch are not obtainable, but in later years (1889-1904) 
the company known as Sheridan's crushed 1,166 tons of ore for bullion valued at £3,368. 

The Golden Point reef, which varies from a hne to 30 in. in width, is apparently a branch 
of the Sheridan, and gave, especially under the bed of the main stream, patches of rich ore. 
It is said to have " pinched " when followed down into the indurated argilhtes. 




1. Mclsaac's Vein 

2. (golden Point Vein 

3. Sheridan Vein & cross veins 



Argillites , grauwackes. ] Tokatea Hill 
and tufaceous mudstones^ Series ' 

Dykes or flows (Andesite) ] First 

\ Period 
Propyl it ised tuffs ii breccias ) Voice nics 



•■V 


\ ' \ 








^: 


+ 




' ■':'•' '■'.■'■■[■' 



Scale of Chains 

10 10 20 

I .... 1 I i_ 



30 



Propyl itised tuffs or flows 



Plan Showing the Puincipal AfRiFKRofs Area of the Lowku Poktiox of Tai'U Vallky. 

Mclsaacs Old Cluint. — This claim, situated in No. 3 gully, on the north side of the valley, 
was worked from three levels. The country rock is argillite, and the vein, according to the 
old reports, consisted of a fissure filled with blue clay, carrpng veinlets and nodules of auri- 
ferous ferruginous quartz. The material crushed in the early days returned from H oz. to 
6 oz. of bullion per ton. This vein, when traced upwards into the andesitic tufl's at the head 
of the gully, showed change of character, the veinstone here consisting of white compact 
quartz. 

It is interesting to note the effect of the nature of the wall-rock on the Hneness of the gold 
in the lower Tapu veins. " Gold " or electrum from argillite areas showed a gold-fineness 
varying from 0-8()6 to 0-722 ; that from andesite areas, a finene:5s varying from 0-752 to 
0-721. * 

Judging from the old official reports, the veins of lower Tapu Valley were found to become 
smaller when followed downwards, and the pockets of pay-ore less numerous. Even if this is so, 
it can hardly be said that mining below the adit-workings wliich have afforded shoots of payable 
ore has received as much attention here as in other less promising locahties. 

In the lower Tapu Valley, particularly on the rather steep slopes of the argillite area 
incised by several small gullies on the northern side of the main stream, the occurrence of 
considerable quantities of auriferous soil and talus was a peculiar feature. The gold was 
" usually flaky and free from quartz, but was sometimes attached to small portions of matrix. 



54 

It was not at all waterworn."* This was evidently a concentration product formed practically 
in situ by weathering agencies from the clayey quartz veins which intersect the argillite rocks. 
Sluicing operations on this blanket of surface material afforded much of the gold of this portion 
of the field. 

Mahara Royal Area. — Another separate area of mineralisation is that in which the now 
abandoned Mahara Royal and other claims are located. This is on the southern side of the 
Tapu Valley, below the main fork of the stream. The p}Titised quartz veins here, which are of 
the usual type, are enclosed in propylitic andesites ; but, although a good deal of surface- 
prospecting has been done, actual mining has been practically confined to one reef — the Mahara 
Royal. 

The Mahara Royal Claim was worked by an EngUsh company from 1897 to 1902 and by 
an Auckland company from 1903 to 1907. Statistics show that a total of 12,910 tons of ore were 
mined and milled for returns valued at £16,769, so that evidently operations proved unprofit- 
able. The mill consisted of a rock-breaker, twenty stamps and twelve berdans, and was 
driven by water-power. The claim was worked to the lowest level practicable by adits, and the 
ore was won from a vein varying from 1 ft. to 8 ft. in width, and, to a much less extent, from 
branching " leaders." Small pockets of bonanza ore were occasionally encountered in the 
principal vein as well as in the smaller branches. According to the mine-plan — the workings 
were inaccessible — the usual quartz-filHng of the vein fissure gives place to clay in the northern 
end of the workings. The block of vein-quartz shown as stoped between No. 4 and No. 5 
levels is 400 ft. in length. Pay-ore is stated to have been followed down some distance below 
No. 5, the lowest adit, but capital for sub-adit exploitation was, in the face of the poor record 
from the adit-workings, not procurable, and the claim was abandoned. 

The Tapu Valley above the main fork of the stream is, on account of the nature of the 
rocks, which belong probably to the Beeson's Island Series, never likely to afford quartz 
veins of a payable character. 

Diehard, Whalebone, and Oturuturu Valleys. 

Andesitic rocks, mostly highly propyUtised, form the country drained by the Diehard, 
Whalebone, and Oturuturu creeks, which enter the sea between Tapu and Waiomo. Breccias 
predominate near the coast-Hne, but flow andesites not unlike those of Waiomo form the greater 
part of the drainage-areas of the streams. 

As the general plan will show, quartz veins are not uncommon. They range in width 
from an inch or so to 6 ft. or 8 ft., and carry either oxidized quartzose veinstones or quartz 
interspersed with one or more of the following sulphides : galena, zinc-blende, copper-pyrites. 
None of the samples taken from the vein-exposures yielded on assay a gold-silver content 
worth noting, although " nil " results were in no case obtained. The only vein which of late 
has received any attention is in the Waipukapuka branch of Whalebone Ci'eek. It probably 
strikes about N. 20° W., and is not, where exposed, very well defined ; its width varies 
probably from 1 ft. to 8 ft. Some blocks of veinstone carry as high a percentage of the 
associated sulphides as the shoot in the Monowai reef, but the gold-silver content of the 
sample assayed did not exceed in value 4s. 6d. per ton. Very little mining-work has yet 
been done in this locality. 

The occurrence of a vein of calcitc in a small branch of the Whalebone entering from 
the north-east some 22 chains below the junction of the Waipukapuka is rather interesting 
and imcommon. The vein was not actually located, but among the shoadings blocks up to 
1 ft. in diameter are not uncommon. In association with the calcite a greenish chloritic 
mineral occurs in certain partings. An assay showed a content of gold 8 gr., and silver 3 dwt. 
10 gr. per ton. 



* Hutton, Report, 1869, p. 33. 



^^^1 


Ulgsy 


Hii^^^B 


p^^ * ■■ 


Bi 




^^^K^^ 




■"C • 


• ' 




-y 


'. 




4.i.i/ - 


'" . - 




>#■ 



-^ « 




Andksitic I5iiK(( i.\-ai;<;i.<jmi;i{atk (Mkkson's Island Skuiks) ovkhi.ai.n hy a Fi.uw A.nuksitk 

TaI'I" VAI.r.KY. 'I'llAMKS. 



Hulhtui Xn. III.] 



[F(ii:t [1. ',lf. 



66 

The tkree streams, Diehard, WTialebone, and Oturuturu, or certain parts of them, afford 
dish-prospects of gold from the gravels, the prospects being best in the Whalebone. This 
WTialebone Valley certainly deserves the further attention of the prospector. 



PuHOi Valley. 

All the rocks examined in the bed of the Puhoi Creek and its branches are propyUtised 
flow andesites similar to those of the neighbouring Waiomo area, but that breccias also occur 
in the head of the valley is indicated by the creek-boulders. The straightiiess of the Puhoi 
Valley from the coast-line up to the main fork of the stream, and the large amount of sUp debris 
coming in from both sides, as well as the close proximity of the Puhoi Creek to the neighbouring 
and approximately parallel Waiomo Stream, are striking features. These strongly suggest 
that the Puhoi has cut its valley along a line of weakness offered by a fault-plane. Gold is 
obtainable in the debris of the Puhoi, and several quartz veins are known to exist, but only 
those included within the Mount Zeehan Claim have received any attention. 

Mount Zfchan Claim (Owners, the Mount Zeehan Gold-mining Company, Auckland). — The 
workings of this claim are situated at and above an elevation of 730 ft. in the southern head- 
water portion of the valley, and are distant (as the crow flies) less than 30 chains from the 
principal workings of the Monowai Claim in Waiomo \'alley. Several fairly well-defined veins 
have been prospected to a small extent. All of these veins have a general northerly or north- 
easterly strike, and show a minerahsation similar to the Monowai vein. Free gold, however, 
occurs in some of the Mount Zeehan sulphide ore to such an extent as to warrant it being 
classed as " picked stone." The association of free gold to this extent with the complex 
sulphides is rather uncommon in the subdivision, but somewhat similar conditions obtain in 
certain rich lenses in the ore-shoot of the Waitangi Claim. The lenses of pay -ore so fre- 
quently octiu" at or in the near vicinity of small faults that mineralisation or at least local 
enrichment must have succeeded the formation of the fault-fractures. The .numerous minor 
faults encountered in this claim are probably subsidiary to the main fault, which is 
considered to strike up the Puhoi \'alley. 

The ore, which contains, in addition to quartz and pyrite, the three commonly associated 
sulphides, galena, zinc-blende, and copper-pyrites, is being classified by hand-picking, but up 
up to the end of 1908 none of this ore had been treated. An analysis by Mr. A. T. Firth, 
Auckland, of rich ore from a small lens intersected in the most westerly vein in the low level 
reads as follows : — 



Silica 










33-90 


Iron 










10-85 


Copper 










7-12 


Zinc 










11-56 


Lead 










13-30 


Arsenic 










1-60 


Manganese 










Trace. 


Sulphur . . 










1202 


Lime 










4-20 


Magnesia . . 










. Trace. 


Carbon-dioxide 










3-44 


Moisture . . 










0-66 


Loss and undetermined 










1-35 



10000 



Assay — Gold, 23 oz. 5 dwt. 4 gr. per ton ; silver, 127 oz. dwt. 4 gr. per ton. 



66 

The position of the claim in respect to the Monowai and old Paroquet workings, the 
favourable character of the country rock and of the vein mineralisation generally, and the 
occurrence in the low level of ore-lenses of higher value than those encountered at shallower 
horizons suggest that satisfactory developments in this little-prospected pioperty would 
not be unexpected. 



fv S.QC. /, 



Monowai Deep" 

S.Q.C.- / 




Scale of Chains 

U3 20 30 



So 



^— Map of principal mining area in the — 
.V Waiomo 8- Puhoi valleys 



Waiomo Valley. 

The whole of the rocks of the Waiomo Valley are andesitic, and, with the exception of 
small exposm-es in the country drained by the headwaters of the stream, they are all propy- 
litised. Flow rocks decidedly predominate in the lower and middle parts of the valley, the latter 
including the principal mining-area. In their altered state, these rocks, which are rather 
coarse-grained, are light-grey or bluish-grey in colour, and usually highly pyritised. The dis- 
position of the flow rocks, and of the few small masses of breccia which occur, is quite indefinite. 

A good many quartz veins have been located in the valley, but so far only those on the 
northern slopes drained by the Paroque!:- and Comstock creeks have proved of importance. 

The existing mining claims are the Monowai (including the old Broken Hills) and the 
Colorado. Older claims were the Paroquet and the Golden Gem. 

The value of the recorded gold-output of the valley is about £19,000. 

Monowai Claim (area, 187 acres 3 roods 39 perches ; owners, the New Monowai Gold 
and Silver Mining Company, Auckland). — The claim was formerly owned and worked by 
companies registered in Auckland and in London. Mining operations in the Monowai Com- 



57 

pany's holding have been contined to exploiting a fairly large reef traversing the spur lying 
between the Paroquet and Comstock creeks, on the northern slopes of the Waiomo Valley. 
This reef strikes N. 20° E., dips westward about 60°, and has a width averaging, say, 20 ft. 
The adit levels, of which there are four in the Monowai Section, have the following elevations 
above sea-level : No. 1, 926 ft. ; No. 2, 890 ft. ; No. 3, 777 ft. ; No. 4, 618 ft. The distances 
driven upon the vein according to the plans are : In No. 1 level. 113 ft. ; in No. 2 level, 240 ft. ; 
in No. 3 level, 665 ft. ; in No. 4 level, 1,380 ft. 

The vein evidently follows a fault fissure, and is practically parallel to a fault con- 
sidered to traverse the Comstock Gully, some 13 chains to the eastward. Evidences of move- 
ment along the vein fissure subsequent to early mineralisation are apparent. In certain places 
what is known as a " buck " foot-wall band of quartz is separated from the more highly 
minerahsed veinstone by a seam of pug or gouge. A crosscut through the vein-formation 
within the limits of the pay-shoot in the lowest or No. 4 level shows a width of 42 ft. (51 ft. 
on horizontal), made up as follows : (1) Clay selvage; (2) hard, rather flinty, sparsely mineral- 
ised quartz — very low gi-ade ; (3) parting with in places a band of pug ; (4) rather favourable- 
looking veinstone — white quartz with dissemination of mixed sulphides, and small irregular 
lenses of the same, carrying an average value of £1 10s. per ton for gold and silver ; (5) quartz 
and country rock intermixed with a few isolated small pockets showing sulphides — very 
low grade. This portion grades iiisensibly into the country rock, and therefore no defined 
hanging-wall is apparent. 




I- 2g'ff"--i-^2'6;'-r-/<?'-i 
Section - Monowai Reef 

The vein, which in the section described is over 40 ft. wide, shows a graduallv diminishing 
width when followed to the upper levels, and is therefore of the in verted- wedge form. 

The pay-shoot, which has yielded almost all the ore crushed from the mine, is nearly 
vertical within the plane of the vein, and is pr()t)ably less than 150 ft. in length. High-grade 
ore was mined from the outcrop down to a little lielow the floor of No. 3 level, a vertical distance 
of about 240 ft. Even within the limits of this shoot, a good deal of selecting of ore had to 
be exercised, as the lenses and bands carrying payal)ly auriferous sulphides were rather ir- 
regularly disposed in the vein, and relatively large blocks of vein-mat crial. ((msidered too low- 
grade to mine, still remain intact. 

The veinstone, as already indicated, is quartz carrying more or lass sulph'de minerals. 
The sulphides are pyrite, galena, zinc-blende, and copper-pvTites, and there also occur 
here and there secondary minerals derived from certain of these. An analysis of concen- 
trated ore from within th.n limits of the pay-shoot gave the following results :* Silica (SiOj), 
67-5 ; copper-p}Tites {CuFoS^), 8-3 ; iron-p}Tites (FeSj), 16 ; galena (PbS), 6-8 ; zinc-blende 
(ZnS). 1-4 : total, 100. There were also traces of bismuth, tellurium, and antimony. Value 
per ton for gold and silver, £4 Os. lOd. 



* r. B. Allen, a-3. IDUU. p. «. 



58 

In mill-treatment the ore is said to have pelded concentrates to the amount of 10 per 
cent. The occun-ence in the more highly minoraUsed ore of small quantities of tellurium 
is noteworthy (see also p. 38). The sulphide ore in places shows a wavy banded structure ; 
again, the sulphides are scattered irregularly as specks, nests, and patches in the quartzose 
gangue. As in the case of the ore of the Colorado reef described on p. 59, veinstone of the 
Monowai containing fresh-looking rather coarsely crystalline galena, zinc-blende, and copper- 
pjTite usually carries low values in gold and silver. In the high-grade ore the sulphide minerals 
are usually finely crystalline or granular, and not infrequently the veinstone consists of honey- 
combed or cavernous white friable quartz, with " clinker-like " bunches and kernels of heavy 
dark complex sulphides. Silver-sulphides undoubtedly occiu' in some of this rich ore. 
Although free gold was seldom or never seen in Monowai ore some of these sulphide " clinkers " 
assayed £400 to £500 per ton, a)id bulk parcels of selected ore shipped to smelters returned 
over £180 per ton net. 

It is significant that most of the rich ore occurs at or in the vicinity of vnags, or in bands 
of the veinstone showing vugs at frequent intervals. 

Beyond the limits of the ore-shoot the quartzose veinstone is hard, in places even flinty, 
and carries a little disseminated p}Tite. The lead, copper, and zinc sulphides are here only 
occasionally noticeable in small isolated patches, and the gold-silver values are very low. 

In each succeeding level from the highest to the lowest the crosscut intei-sected the reef 
further and further southward from the main vertical pay-shoot, and this accounts for the more 
extensive drifting on the reef in the lower than in the upper levels. XotwithstandLng the length 
of drifting done (1.380 ft.) at No. 4 level, it cannot be affirmed that the reef has been system- 
atically prospected, and it is somewhat surprising that between the main crosscut and a 
crosscut projected through the reef from the drift some 1,300 ft. northward and nearly mider 
the line of the ore-shoot, no cuts have been put in to test the width and value of the vein- 
stone. The drift is in places within the vein-formation, but at what particular part of its 
cross-section is unknown ; again, it follows one wall of the vein , or is altogether within country 
rock. That minor ore-shoots do occur was shown by the operations of the Ferguson Mining and 
Smelting Company, who were working the mine under an option to purchase. At a point 
over 1,000 ft. south of the ore-shoot in the No. 4 level high-grade ore was discovered only 
a few feet from the drift in the eastern section of the reef. This has been stoped for about 
60 ft. above the level. The ore-pipe here is nearly vertical within the plane of the vein, is 
only a few feet in length along its major diameter, and is connected with a vug or cavernous 
band in the vein-formation. The mineralisation is precisely the same as that in connection 
with the main ore-shoot. 

An assay of the rich "clinkery" siilphide material from this pipe yielded: Gold, 
2oz. 17dwt. 23 gr. per ton; silver, 62 oz. Idwt. 8gr. per ton. Tellurium was present to the 
extent of 0-03 per cent. 

In the Broken HiU Section of the property a little work was formerly done (by a separate 
company) on the Monowai vein, and a Umited amount of high-gxade ore was raised. The 
elevation of the highest workings is 1,125 ft. — i.e., over 500 ft. above the Monowai low level. 
The fact that the vein here — though well defined — is in places not more than 18 in. wide 
suggests that its original apex may not have extended far above this horizon. The work- 
ings here were mostly inaccessible, but two samples from the old ore-dumps gave, on assay : 
(1.) 11 dwt. 23 gr. gold per ton ; silver, 9 oz. 12 dwt. 4 gr. per ton. (2.) 8 dwt. 19 gr. gold 
per ton ; silver, 8 oz. per ton. 

The treatment of the Monowai oie has, on the whole, been unsatisfactory, and it would be 
difficult to speculate as to what was the percentage recovered of the actual gold-silver content 
of the ore. It was certainly low. Official reports show that from the year 1894 to 1903, 11,702 
tons were treated for a return valued at £13,254. From the Broken Hill Section 98 tons 
were treated, from 1889 to 1894, for 60 oz. of bullion (value not recorded). 



69 

The Monowai mill comprises ten stampers (about 850 lb. each), amalgamating-tables, 
three Union vamiei-s, and a small badly arranged cyanide plant. A small suction-gas plant 
was installed to supplement the power derived from a Umited water-supply. 

The future prospects of this property are, in the absence of reliable records as to the 
actual value of the ore already mined, difficult to gauge, but it is certain that notwithstanding 
the occurrerce of rich ore pipes and lenses it resolves itself on the whole into a low-grade proposi- 
tion. Operations below No. 3 level have disclosed low-grade ore on the downward prolongation 
of the ore-shoot of the upper workings, and the advisability of entailing the heavy expense 
of opening up the veui at a greater depth is, without further data, open to question. That the 
vein will persist downwards there is no reason to doubt ; and the sinking of well-directed 
boreholes may prove the most judicious way of initially prospecting the vein at deeper horizons. 
On the levels of the existing adits practically nothing has been done northward of the main ore- 
shoot — that is, between the Monowai and Broken Hill workings — and this block offers induce- 
ment for legitimate prospecting. The chances of discovering further small shoots or pipes 
of payable ore southward of the main shoot, in addition to the one located by the operations 
of the Ferguson Company, have already been indicated. 

Colorado (Old Comstock) Claim (owners, the Ferguson Mining and Smelting Company). — 
The principal vein occurs eastward of Comstock Creek, near its junction with Waiomo Stream. 
This vein strikes N. 32° E., dips 65° N.VV'., averages about 3 ft. in width, and has been mined 
by adits from the slopes of Comstock Creek Valley and from the edge of Waiomo Stream, 
a few chains eastward. The stopes on the vein have been carried westward to a point near 
the bed of Comstock Creek, where broken slidy ground was encountered, and all efforts to 
locate the vein westward of this creek have proved futile. The broken ground here revealed 
by mining, and the remarkable straightness of the Comstock Valley, are strong evidences that 
this valley is cut along a fault-line. From the behaviour of the vein when approaching this 
fault it is doubtful if it has an offset counterpart on the western side of the fault. 

The mineralisation in the Colorado is precisely the same as that in the Monowai, but the 
vein never carried values in gold and silver, except very locally, as high as the Monowai vein. 
The greater part of the pay-ore was extracted from a block, in the two upper levels, extend- 
ing from the fault to a point less than 50 ft. eastward. An assay (1) of a sample of the finely 
cr\-stalline sulphides and their alteration -products from No. 2 level compared with an assav (2) 
of the fresh-looking coarsely crystalline sulphides from No. 3 level is interesting. Approxi- 
mately the same amount of siliceous gangue was present in each case. 

(1.) (2.) 

Lead . . . . 13-86 per cent. 19-33 per cent. 

Copper .. 2-23 „ 2-47 

Zinc .. .. 4-82 „ 10-12 

Gold . . . . 1 oz. 3 dwt. 22 gr. per ton oz. 2 dwt. 12 gr. per ton. 

Silver 23 oz. 17 dwt. 15 gr. ,, 6 oz. 17 dwt. 8 gr. 

The ore mined by the original Comstock Syndicate was hand-picked and shipped to 
the Dapto smelters (Australia). The net return from the first parcel (2 tons) was £87, and 
from the second (3 tons) was £88. From 30 to 40 tons were crushed and concentrated at 
the Monowai Company's mill, and the concentrates — about one-tenth of the bulk ore — yielded 
on smelting (at Dapto) about £14 per ton net. 

Paroquet Claim. — The old Paroquet Claim hes at an elevation of over 1,100 ft., in the 
country drained by the headwaters of the creek of the same name. As all the workings are 
in a state of collapse, examination was impossible, and most of the data here given has 
been obtained from the Mines Reports of 1887-89. In this area the first payable gold found in 
Waiomo was discovered in June, 1886, by Lowrie Bros, and Plummer. The vein was well 
defined, and proved to have an average mdth of 3 ft., with a shoot of pay-ore about 90 ft. 
in length, which continued downwards a Uttle over 100 ft. below the outcrop. 



60 

The tirst 33 tons mined iiuni the outcrop portion — free nulhng-ore — returned 337 oz. ol 
gold, and in ail about 1,400 oz. were obtained by the original prospectors. The company, 
which subsequently acquired the ground and erected a twenty-stamp mill, had a short life, 
owing, it is stated, to the non-persistence of the pay-ore in depth. Small fragments of 
veinstone on the dump of the lowest level show the same sulphide minerals as at the 
Monowai — pjTite, galena, chalcopyrite, and zinc-blende, but only as very sparsely dis- 
seminated small crystals throughout the white quartz. 

This Paroquet vein, which yielded the richest outcrop ore in Waiomo, lies midway be- 
tween the Broken Hill Section of the Monowai vein and the Mount Zeehan veins of Puhoi 
Creek, which carry ore similar to the Monowai. It is, furthermore, less than 20 chains from 
the low-level workings of the Mount Zeehan, so that an examination of the Paroquet vein at 
the lowest level, where payable free-milhng ore was Reported to have given out, and where 
sulphide ore evidently began to appear, would have been particularly desirable. 

Golden Gem Claim. — The vein of the Golden Gem Claim is situated at an elevation of 
750 ft. on the spur, about 30 chains north-west of the junction of Paroquet Creek with Waiomo 
Stream. The workings have collapsed. The records show that in 1888 and 1889 some 371 
tons of completely oxidized ore were mined and milled from a vein varying from 6 in. to 2 ft. 
in width for a return of 312 oz. of gold-silver bullion. A sample of veinstone taken by the 
writer from the old dumps assayed only 9s. per ton. The gold of the vein is reported to have 
occurred in an extremely fine state of division. It may possibly have been liberated from 
the sulphides common to the Waiomo area, but only a few remnants of pyrite were seen in 
the quartz. 

PuRU Valley. 

The Puru Stream drains an area of roughly 9 square miles. All the rocks are more or 
less propyhtised ai\desitic flows and breccias, and, with the exception of those forming the 
headwater country (probably belonging to the Beeson's Island Series), they are referable 
to the " First Period." 

Certain of the " First Period " breccias present a striking resemblance to those of 
Tararu Creek, near Thames. The veins are apparently confined to these older andesitic rocks, 
and are fairly numerous, although, unfortunately, none of them have given returns which 
could be considered profitable. The lead, copper, and zinc sulphides so common in the 
veins of the Waiomo and other areas further northward are seldom or never seen in the 
veins of Puru. Here only pyrite and its oxidation products are noticeable in the quartzose 
gangue. 

No mining is at present in progress in the valley, but between 1893 and 1903 prospecting 
and mining were carried on from time to time. The record is : Tons crushed, 2,195 ; bulhon 
produced, 611 oz. ; approximate value, £1,670. This output was derived almost entirely 
from the claim worked by the Puru Consohdated Company. Of the other old claims, only the 
Puru Big Reefs need be mentioned. 

Puru Consolidated Claim. — The workings of this abandoned claim are situated at an 
elevation of 1,300 ft. to 1,400 ft. in a small southern branch of the Puru, and in fairly steeply 
sloping thickly bushed country. The entrances to the two adit levels which gave access to 
the workings have collapsed. The principal reef, which strikes about N. 50° E., is reported 
to range from 1 ft. to 3 ft. in width. It was enclosed between fairly well-defined walls, and 
few stringers or branching veins were found to junction with it. No definite ore-shoot was 
recognised, the patches of good ore enclosing occasionallj- a little " picked stone " being dis- 
tributed irregularly throughout the blocks worked. The gold was " showy," and the crushings 
never came up to expectations. Wires or threads of gold up to 9 in. in length were obtained 
on more than one occasion from cavities in the vein in the upper level, but not in the low 
level. This suggests a secondary enrichment of the ores nearer the surface by meteoric waters. 



61 

Other veins besides the one described ware located on the property, but gave very little 
gold. 

The mine-workings were connected by an aerial tram 33 chains long with a mill consist- 
ing of ten stamps and two amalgamating-pans, situated near the main creek. The mill, which 
was worked by water-power, has been removed, as the claim proved unpayable. 

Puru Big Reefs Claim. — A large reef, striking N. -15° E. and dipping S.E. at high angles, 
has been cut through in a drive entering from the northern bank of the main creek at an eleva- 
tion of about 630 ft. By far the greater part of the vein-formation consists of silicified pro- 
pylite with isolated bunches or lenses of quartz, but a fairly solid 'band of quartz forms the 
foot-wall section. In all, the formation measures about 50 ft. across. Iron-oxides stain the 
quartz throughout, and in places remnants of pyrite are to be seen. The reef was carefullv 
sampled in sections from the hanging-wall to the foot-wall. Excepting the band of quartz 
on the foot-wall side, which has been driven on for some distance and assays 15s. ?d. per ton, 
the vein-material gives no higher values than 28. 6d. per ton. An outcrop of the same reef, 
near the creek, about 2 chains below the drive mentioned above, gave a sample assaying 
10s. 4d. per ton, and a hanging-wall branch about 3 ft. wide, a sample assaying 15s. 4d. per ton. 
Very little work has been done on the reefs in this claim. 

From several of the numerous other veins in the valley samples were taken, and although 
on assay " nil " results were in no case reported, the value of no sample exceeded 2s. per ton. 
Fine gold is, however, ol)tainal)le in many places by carefully panning the stream debris. 

Speaking generally concerning the Puru Valley, it would appear that discontinuance of 
prospecting operations is due to the past history of mining ventures in the locality rather 
than to lack of surface prospects. 

Otohi Valley. 
The Otohi is the largest of the creeks entering the Firth of Thames between Puru and 
Tararu. The altered andesitic rocks of its valley, which resemble those of the neighbouring 
areas, carry several quartz veins. Some of these have been prospected to a limited extent, 
but without success. They range in width from a few inches up to 2 ft. or 3 ft., and generally 
carry oxidized veinstones. Samples taken for assay from these yielded values of only a few 
pence per ton in each case. From a vein about 2 ft. wide occurring in the head of the valley, 
at an elevation of 1,470 ft., and carrying pyrite, copper-pyrites, zinc-blende, and galena, a 
gold-silver content of 3s. per ton was reported. In the debiis of the main creek fair dish- 
prospects of gold are obtainable up to about 80(J ft. above sea-level, and a few " colours " 
beyond this point. 

T.\RARu Crekk Valley (above Ohio Junction). 

Eclipse f'lnim (present owners, the Tararu Mines (Limited). Auckland). — The Eclipse Claim 
(area, 200 acres) includes the old Vulcan and other holdings, situated, as the map will 
show, in the upper Tararu Creek Valley, at elevations ranging from 1,2(W ft. to 1,400 ft. 

The actual gold-silver output of the claim prior to 1807 is unknown, but it is stated that 
the Vulcan Gold-mining Company (Auckland) obtained about 8,0<)0 oz. (value, .say, £22,0(X)) 
from the upper 100 ft. of a certain section of the Vulcan vein. From 1897 to 1903 the claim 
was worked by the Eclipse Gold-mining Company (Limited), under the supervision of the 
Thames Exploration Syndicate (London). 9,932 tons of ore were crushed for 5,219 oz. of 
bullion, value £14.654. From 1904 to 1906 the New Eclipse Company (Auckland) raised 
1,.356 tons of ore for 1,192 oz. l)iillion, value £3,312. Total value of output (1897-1908), 
£17,966. 

The claim was worked from two main adit levels, which are vertically 66 ft. apart, and 
from smaller outcrop drives. The mine was connected with a battery (ten stamj)s and six 
berdans — water-power) by aerial tram 7,4(JO ft. long, but the whole of this plant has been 
dismantled and removed. 



62 

No profits were earned by the companies which worked the property subsequent to the 
year 1897, although in certain years the value of the bullion raised more than covered the 
working-expenses. The long distance between the mine and the battery, and the fact that the 
aerial tram required steam-power to operate it, rendered handUng and transit of ore expensive. 

The country rock of the claim, as far as could be observed, is entirely a propyHtised ande- 
sitic flow rock. That of the low level is decidedly uniform in texture, highly pyritised, and would 
be generally regarded as a very favourable class of country. 

A single vein of some considerable size which divides into two or more branches has been 
the locus of past mining operations. The general trend of this branching vein is about N.E.- 
S.W., and its dip is to the S.E. 

Owing to the collapsed state of portions of the workings, underground examination was 
impossible, and the following remarks are therefore somewhat general. 

The principal veins worked were the No. 1 or Vulcan, averaging 6 ft. to 7 ft. in width 
(a branch of the main reef), and the Cross reef, averaging 3 ft. At the " Mid " level 800 ft. 
of driving was done on the Vulcan. In the low level a similar distance was driven upon vein- 
quartz, partly on the main reef and partly on the Vulcan branch. 

According to the Mines Report for 1898, the Vulcan reef carried very good prospects 
over a horizontal length of 360 ft. ; but from the stoping-plans it would appear that the main 
shoot of ore was shorter than this by about 100 ft. This shoot was nearly vertical, extended 
to both sides of the junction of the Cross reef, and was followed from the outcrop to a vertical 
depth of about 200 ft. Good ore with pockets of " specimen stone " were, it is reported, 
obtained down to within a stope or two of the back of the lowest level. 

The vein-material consists in the main of quartz carrying a variable percentage of pyrite, 
and occasionally very small amounts of copper-pyrites and zinc-blende. It generally pre- 
sents a massive appearance, but curly banded structures are observable in places, and occasion- 
ally the quartz is obviously pseudomorphous after calcite. Country rock silicified and other- 
wise mineralised frequently forms part of the vein-material. Isolated patches of " specimen 
stone " occurred within the limits of the ore-shoot, and these contributed largely to support the 
average tenor of the ore. 

With the available data it is difficult to speculate upon the future prospects of the EcUpse 
Claim, but several local mining men formerly connected with the working of the mine consider 
that the ground was prematurely abandoned. Exploration, however, below the lowest adit 
means shaft-sinking and pumping, and would require considerable capital. From an inspection 
of the plans, further prospecting at the existing adit levels would be advisable prior to deciding 
upon a heaviei: expenditure. It appears that the Vulcan is the foot-wall branch of a larger 
reef, and that this larger reef has never been prospected in a position corresponding to that 
at which the Vulcan carried its ore-shoot. An offset crosscut in an east-south-easterly direc- 
tion from the hanging- wall of the Vulcan near the point of intersection of the Cross reef would 
afford an indication of the prospects in this direction. 

The eastern extension of the Vulcan reef is seen outcropping on the graded track about 
200 ft. north of the old shaft. The veinstone here shows a curly banded structure, and carries 
pyrite, galena, and copper-pp-ites, also gold and silver to the value of 8s. 6d. per ton. Although 
the " Mid " level has been advanced under this point, Uttle further prospecting appears to 
have been done in this direction. 

Scandinavian Claim. — The Scandinavian Claim (area, 54 acres) is being worked by the 
Scandinavian Gold-mining Company (Auckland), and is situated on the steep northern slopes 
of the upper Tararu Valley, at elevations approximating 1,900 ft. 

Some considerable amount of gold was, it is stated, obtained in the early days fi'om out- 
crop workings ; but since 1887 the total yield recorded was valued at only £805, derived from 486 
tons of ore. 



63 

The country rock is a propylitised andesite, with, in places, remnants (" haid bars ") of 
dark little-altered rock. Three veins with a general north-east - south-west strike have been 
exploited. These are the Black reef, Lowrie's reef, and the Nightingale reef. The last named 
appears to be the parent vein, and the Black reef and Lowrie's are probably " droppers " or 
branches which would be found to junction with it on its hanging- wall side, about 200 ft. below 
the present No. 10 adit. 

Lowrie's reef afforded almost all the gold won from the claim, but the deeper workings here 
have so far failed to reveal veinstone assaying more than £1 5s. to £1 15s. per ton ; and this 
is unpayable, considering the position of the claim and the absence of crusliing-facilities. The 
outcrop patches of high-grade ore were apparently the result of repeated concentrations of 
the gold-silver content of the primary veinstone during the downward migration of the belt 
of weathering. 

The primary ore of the Scandinavian veins and of many of the other veins in upper Tararu 
is characterized by the splendent lustre of the pyrite associated with the quartzose gangue. 
The sulphides of zinc, copper, and lead are of infrequent occurrence in the Scandinavian area. 

Chicago Claim. — This old claim is located on the northern side of the Tararu Stream, 
at an elevation of 1,050 ft. 

A quartz vein ranging up to 7 ft. in width and several smaller branches were worked from 
1894 to 1900. 

The proprietary company erected a battery of ten stamps, but, after crushing some 202 
tons of veinstone for an unpayable return of bullion valued at £167, abandoned the venture. 

Temple Bar Claim. — This claim, situated in the valley of Argosy Creek, a northern branch 
of the Tararu Stream, was until recently worked by the Temple Bar Company. A gold-return 
valued at £113 was reported in 1903 as the result of the treatment of 5 tons of ore. In the 
lowest level (elevation 1,060 ft.), propylitised flow and brecciated andesites have been pene- 
trated, and a small poorly defined vein intersected. The prospects of improvement are un- 
favourable. Other veins have been located, but none of these have so far afforded encouraging 
results. 

Argosy Claim. — This is an old abandoned claim at the source of Argosy Creek, the 
elevation of the locaUty being 1,750 ft, 

The workings are inaccessible. Old reports state that several veins varying up to 2 ft. 
in width were intersected, and certain of them afforded small pockets of rich stone. The 
only recorded returns were obtained in 1897 and 1903, when 4| cwt. of ore yielded gold-silver 
bullion which sold for £132. 

The country rock on the dump is a propylitised andesite of uniform texture and favourable 
appearance. A sample of the veinstone, which consists of hard white quartz with vitreous 
bluish-grey patches and streaks carrying a good deal of pyrite, gave on assay a gold-silver 
value of 153. per ton. 

Kaimarama Valley. 

Only the upper portion of the valley of Kaimarama Stream, which flows into Whitianga 
Estuary, lies within the Thames Subdivision. Prospecting tunnels were driven in the lower part 
of the valley some years ago, with the object of locating the source of certain loose blocks of a 
milky-white finely crystalline auriferous quartz, which was reported to have been found in the 
vicinity. No parent reef was ever discovered, and no prospecting-work is now being done in 
the valley. 

The vein-bearing area of the Kaimarama is practically confined to the ridge separating 
the main stream from Mclsaac's Creek, a branch of the Mahakirau. Here large sheadings 
and " bluffs " of quartz are conspicuous, as well as a few fairly definite veins showing a general 
north-easterly strike. None of the quartzose samples collected assayed more than Is. 4d. 



64 

per toll for gold or 3s. 6d.. per ton for silver, nor can scarcely a " colour " of gold be got in 
panning the alluvium of the small streams scoring the vein-bearing country. The prospects 
of anything payable being discovered above the source of the loose blocks of ore mentioned 
therefore seem remote. The marked propylitisation of the rocks of the greater part of the 
valley and the abundance of p}T:ite and of silicified bands in the country rock have led to 
many small prospecting tunnels being driven, but without success, and it seems that the hydro- 
thermal waters which effected the rock-alteration were deficient in the precious metals. 

Waiwawa and OrxAROA Valleys. 

The Waiwawa, with its various tributaries, and tl c much smaller Omiaroa Stream (Mill 
Creek) and its branches drain a tract of country measmung about 49 square miles, and extending 
eastward from the crest of the main range to the boundary of the subdivision, and northward 
from Table Mountain to Kaimarama Valley and Whitianga Estuary. The rocks of this area 
are almost altogether andesitic flows and breccias belonging to the Beeson's Island Series, but 
vounger intrusive andesites and also rhvohtes occur in the south and east. 

The mining prospects of this relatively extensive area can be summed up in few words. 
The chances of important metaUiferous veins being discovered are remote. This con- 
clusion has been arrived at after a study of the rocks and a careful examination of the 
alluvium of the various watercourses. Within the Waiwawa watershed small quartz veins were 
located in Jerry's Creek and in No. 69 Creek and at the mouth of Settler's Creek (see map). 
Those in the first-named creek showed a Uttle stibnite (antimony-sulphide) in the quartz gangue, 
but like those in the other two locahties carried practically no gold nor silver. Bands of rock 
showing some sihcification are occasionally seen in local areas of propyUtisation, but are of 
no importance. A trail of detrital gold was discovered in Jerry's Creek and in Prospect Creek, 
but in each case it was traced to a small clay-filled fissure in the rocks. In all other cases 
dish-prospecting only served to confirm the general barrenness of the area. 

Kauaeraxga Valley. 

That portion of the drainage-area of the Kauaeranga River which hes within the Thames 
Subdivision measures about 37 square miles. The predominating rocks here are andesitic 
flows and breccias of the Beeson's Island Series, while, as in the Waiwawa area, younger intru- 
sive andesites and tufaceous and massive rhyoUtes also occur. In addition, andesites, refer- 
able to " First Period," cover an area lying within the tributary valley, Mangakirikiri. and 
possibly extending into the neighbouring valley. Mangarehu. 

Of the whole stretch of the Kauaeranga watershed lying within and, it may be added, 
bevond the hmits of the Thames Subdivision, the Mangakirikiri \'alley and its vicinity alone 
presents possibilities as a mining-area. Beyond the limits of the Mangakirikiri Valley the 
same general remarks made in reference to the barren Waiwawa Valley also apply to the 
Kauaeranga. A httle gold is shed into the headwaters of certain branches of the Hihi and 
other creeks from sparsely auriferous impregnations in altered tufaceous rhyolites, but these 
rhyolites, on being prospected, have proved of no importance. 

Siliceous sinters occurring as " blows " and fairly extensive sheets are conspicuous in 
the country Iving between the Mangakirikiri and the Whangaiterenga streams on the western 
side of the Kauaeranga. General samples, however, collected from the most favourable- 
looking of these sinters and from associated iron-stained and silicified andesites gave on assay 
no traces of the precious metals. 

Within the Mangakirikiri Valley gold-mining has been practically confined to the countrv 
drained by Otanui Creek, and the only claim at present being worked is the Otanui Consols. 
Some prospecting for cinnabar has been done in the lower Mangakirikiri 




Kal'.\kii.\.\(;a Vai.i.ky. Tiiamk 



U nil < tin S». III.] 



[Fare p. Il!f. 



65 

Otanui Consols Claim. — The Otanui Consols Claim, which is owned by an Auckland 
syndicate, comprises what were previously several small holdings^ — the Eureka, Comet, 
Oriental Nos. 1 and 2, Victoria, Bonanza, and others. Fifteen thousand pounds sterhng 
perhaps represents the approximate value of the gold raised from these holdings prior to 
1887 (the actual figures are not recorded). From 1887 to date 1,245 tons have been crushed 
for 547 oz., valued at about £1,505. 

The country rock of the Otanui Consols Mine is andesitic, and consists of fine-grained 
breccias and interbedded flows, all considerably altered. These rocks present a striking re- 
semblance to those in certain mines of Karaka Creek, Thames. 

Several quartz veins, varying in width from a line to 4 ft. or 5 ft., have been located. 
These veins vary in strike from N. 35° E. to N. 61° E. Their dips are to the N.W. or S.E., 
and those with the former inclination have proved the more productive. The veins inter- 
secting the breccia country consist largely of puggy crushed rock with lenticles and bunches 
of quartz, and show occasionally small filaments and flakes of gold ; but, so far, none of these 
veins have proved very productive. The Eureka vein, which yielded most of the Otanui 
gold, could not be examined, as it was not, at the time the area was surveyed, cut at the lowest 
level, and the old shallower workings are inaccessible. From reliable information it would 
appear that this vein, where the ore-shoot occurred, intersected propylitiscd flow andesite 
{" like Kuranui Hill country Thames "), and further eastward on striking into the breccias — 
" mottled country " — the values gave out, although the vein persisted. The main ore-shoot 
of this Eureka vein, which varied in width from 4 ft. to 5 ft. near the outcrop and from 18 in. 
to 24 in. further down, measured from 1(X) ft. to 120 ft. on the horizontal, and was mined 
from the surface to and a little below No. 2 level — say, 100 ft. below the outcrop. Going west- 
ward, the propylite graded into hard dark andesite, and, although a little gold was seen in the 
veinstone even where enclosed in the hard rock, it here became, as might be expected, 
unpayable. 

The prospecting syndicate has sunk a small shaft ; and from it a drive, which will measure 
in all about 800 ft., is in progress to intersect the Eureka vein about 150 ft. below the old 
No. 2 adit. As the same, if not sHghtly more, backs could have been obtained by driving 
an adit level 1,600 ft. in length, this course would have been preferable, and would have given 
permanent access to a considerable stretch of vein-bearing country. 

The original Eureka Company erected a mill consisting of ten stamps and three berdans 
at the junction of Otanui Creek with the Mangakirikiri ; but this has long since been removed. 

Auriferous country has some extension both to the north and to the south of Otanui 
Valley. This fact is evidenced by the " colours " of gold which can be washed from the 
alluvium of the other creeks draining the western slopes of the Mangakirikiri Valley. Very 
little prospecting has, however, been done in these localities. The indications in the neigh- 
bouring Mangarehu Valley are much less promising. 

The Cinnabar Occurrences of Mangakirikiri (Kauaeranga). — The exact location of the 
cinnabar occurrences is at an elevation of 500 ft. to 600 ft., on the ridge 20 chains south- 
westward of Mangakirikiri Stream and one mile (as the crow flies) from the junction of this 
stream with the Kauaeranga River. The mineral is associated with bands of siliceous sinter, 
and occasionally with the more silicified and brecciated portions of the propylitiscd andesites 
which enclose these bands. 

The few hundredweights of ore raised appear to have been mined from a band exposed in 
a small surface-adit. This band, which dips S. 10° E. at very low angles, ranges from 1 in. to 
10 in. in width, and carries a few lenses of cinnabar-ore about 1 in. or so in width. These 
lenses notably occur in the band at or near the intersections of irregular highly inclined clay- 
filled fractures. The deposition of the cinnabar, however, certainly appears to have been 
contemporaneous with that of the compact sihceous sinter. The quality of the ore mined 

5 — Thames. 



(5(i 

was satisfactory — some of it carried 25 per cent, of mercury — but the quantity was far too 
limited to pay. An assay of the quartz sinter for gold and silver gave a " nil " result. An 
adit was driven 50 ft. below the one mentioned, and was connected \\'ith the latter by a rise. 
Presumably the discovery of further bands was expected, especially in rising, as it is difficult 
to see how the almost flat-lying band prospected in the upper level could have been inter- 
sected below in the limited amount of driving done. 

McKay,* who examined the locahty while prospecting- work was in progress, refers to 
an outcropping surface band 3 ft. to 4 ft. thick dipping eastward from 40° to 48° ; but this 
was not seen by the writer, owing probably to the thick scrubby vegetation which now covers 
the country. 

The cinnabar-deposits are likely to be confined to a comparatively limited area enclosing 
the locality prospected, and the chance of locating further ore-bearing sinter- bands, or the 
more highly inchned pipes or veins by which the mineralising solutions probably ascended, 
would be the only inducement for further prospecting. 

KiRiKiRi Valley. 

The only portion of the Kirikiri Valley which is of any importance from a mining point of 
view lies in the actual headwaters, and outside the boundary of the subdivision under re\aew. 
In this unexamined portion of the valley are the veins of the Kirikiri Mine. 

The rocks of the part of the Kirikiri Valley lying within the Thames Subdivision are ande- 
site flows and breccias (all apparently portions of the Beeson's Island Series), and also tufa- 
ceous rhyolites of younger age. Quartz veins of any considerable definition and persistence 
apparently do not occur. Silicified bands are found in the altered rhyolites and to a less 
extent in local areas of propylitisation in the andesites. 

A little gold is being shed into the creeks from the disintegration of the altered rhyoUtic 
tuffs and sihcified bands enclosed therein. It would appear that here, as at Puriri and else- 
where, the thermal solutions which affected the alteration of these rocks were to some degree 
auriferous. Gold has been sparingly deposited throughout portions of the rock-masses, 
but in apparently no case has a sufficient concentration of the metal been effected to afford a 
workable deposit at any locality within the area. 

Some of the bedded tufaceous sands and muds (rhyohtic) occurring in the bed of the 
main stream at the junction of Hokimai Creek show in certain laminte streaks of pjTite. 
Picked samples of these p\Titised portions were selected for assay, and yielded a gold-content 
equal to 2J dwt. per ton, and a silver-content of Uke amount. This is the highest assay 
obtained from the various samples collected from the veins and impregnations of the valley, 
but it is of interest as showing the nature of the auriferous deposits from which the gold of 
the stream-alluvium is derived. The samples selected from the various silica bands discovered 
in the higher country gave in no case a gold-content of more than a few grains to the ton. 

Wharehoe and Matatoki Valleys. 

Neither the Wharehoe Valley nor the adjoining Matatoki Valley is, in the opinion of the 
writer, ever likely to afford a metalliferous deposit of economic value. The rocks of both 
these valleys are Beeson's Island andesites and yomiger tufaceous rhyolites. 

Puriri Valley. 
The greater part of the Puriri mining-area — that which includes the Champion and other 
claims — is located in the high country drained by the Apakura or southern branch of the 
Puriri, and lies beyond the limits of the area examined. 

* " Report on the Occurrence^ of Cinnabar in the Kauaeranga Vallejr. Tliames Coynty," C.-9, 1898, p. 8. 



Tc accompany Builetuv y^ /O . 




By Aulhcrity ■ John Uackay, GovernitUKt Printer. 



aoo a 'o, f^3_ 



67 

Both " First Period " andesites and Boeson's Island andesites as well as younger rhyolites 
have development in that portion of the valley under review. 

The lower part of the spur which separates the Apakura and Kotoreputuai, the two main 
branches of the Puriri, consists of older andesites, and is the only vein-bearing area worthy 
of note in the country examined. Here is located the Joker and several smaller veins. The 
Joker is a fairly strong reef striking about N. 60^^ E., and dipping south-eastward at high angles. 
It is of the ordinary typo — quartz carrying more or less p}Tite — ranges from 6 in. to -i ft. 
in width, and has been worked from three or more adits, spaced between elevations of 750 ft. 
and 1,050 ft. Nearly all the workings are in a state of collapse. 

Both English and local capital have been spent in prospecting and development work 
in this area, and, although certain small blocks on the Joker and other veins proved pro- 
fitable, mining operations have resulted in a loss. The output prior to 1887 is not recorded ; 
but since that year statistics show that 1,860 tons of ore were treated for 1,545 oz. of gold- 
silver bullion, valued approximately at £4,165. The titles of the principal contributing claims 
were the Miner's Right, Bedford's Hit or Miss, Old Prospectors, Puriri, Union Jack, and 
Surprise. The others wore the Burdett, Central, Dover Castle, Empress of India, Lucky Chance, 
Mauvoline, and Ngawhakapoupou. It is beUeved that most of these, if not all, were located 
in the area mentioned. 

The general verdict with regard to Puriri is that the pay-ores are confined to small pockets 
or shoots at or near the outcrop of the veins, but that at greater depth these shoots become 
less numerous, or give out altogether. It should, however, be stated that mining hi the locality 
has been carried on in a desultorj' fashion ; and it is very questionable if the capital of certain 
of the prospecting companies has been expended to the best advantage. 

As in the Kirikiri and Kauacranga valleys, the tufaceous rhyolites in local areas of siUci- 
fication carry a httle gold, but such occurrences are of no considerable importance. 

Omahu Valley. 

The lower portion only of this valley falls within the area examined ; and, as all the mining 
claims are located in the Tairua-Waihi Subdivision, immediately to the eastward, they do 
not come within the scope of this report. 

The Mining-area and Mining Clalms at and nkar the Town of Thames (Thames 

Special Arpu). 

A description of the mining claims of the Thames centre itself involves a special con- 
sideration of the salient geological features of the area enclosing them. This particular area, 
which has been the subject of many geological notices, presents difficult problems both in respect 
to the structure of its rock complex and the localisation of its pay-ores. Many of the older 
underground workings, the examination of which might have thrown Hght on obscure points, 
are unfortunatelv now inaccessible. During the course of the writer's survey the drainage of 
the various foreshore mines from the Kuranui to the Saxon was only ef[ect«d to a depth of 
425 ft. below sea-level ; and little information is recorded regarding even the precise nature 
of the country rock of the main " 640 ft." level crosscut which traverses a considerable section 
of this area. 

Boundaries of the Special Area. — The special area here described, which measures about 
six and a quarter square miles, extends southward from Tararu Creek and its tributary the 
Ohio to Hape Creek. In plan it is roughly triangular in shape, the foreshore of the harbour 
representing the base, and the Look-out Rocks the apex of the triangle. 

The physical features of this block of country are indicated in the contour map which 
accompanies this report, 

5'— ThameB, 



68 

The Oldest Rocks. — Within the area outhiied, rocks older than the Tertiaiy volcanics are 
not visible. At Eocky Point, however, about 50 chains northward of the mouth of Taraiu 
Crcok — i.e., about two miles and a quarter from the Town of Thames — a small patch of slaty 
shales or argillites with interstratified folsitic tuffs and mudstones (Tokatea Hill Series) is 
exposed ; so also at the Quarry, in the same locality, is a remnant of the Jurassic con- 
glomerates which unconformably overlie them. These stratified rocks constitute the base- 
ment or floor upon which the andesitic rocks of Thames rest, or through which they have 
been extruded. 

At Thames the basement-rocks were ascertained by the Kuranui-Caledonian borehole, sunk 
near the entrance of the Moanataiari tunnel to underUe the andesitic series apparently on 
the foot-wall side of the Moanataiari fault at a drilhng-depth of 1,240 ft. — say, 1,170 ft. below 
sea-level. The general slope-angle of this floor of old rocks from Rocky Point to this bore- 
hole is not more than about 7° ; but considerable irregularities on this ancient surface can, 
of course, be expected to exist. 

The Vein-hearing Rocks. — Tertiary volcanics of the " First Period," both andesitic and 
dacitic in character, constitute, with the exception of unconsohdated alluvium, the whole 
of the rocks Aasible in the area. 

Viewed broadly, two markedly different but obviously related rock-formations are here 
recognisable in this series — (a) a complex of alternating andesitic and dacitic lavas and breccias 
with associated dyke-intrusions ; (6) a relatively extensive area of non-brecciated andesite 
of considerable uniformity' in mineralogical character — in the main, probably a single heavy 
lava-flow. This has been designated the " Premier " flow. 

The map of the special area shows the approximate surface-boundaries of these two 
formations of the volcanic series ; the sections show the general dispositions of the formations 
as near as can be determined from the rather limited e\adence available. 

(a.) The Andesitic Flow and Breccia Complex. — The flow and breccia complex has con- 
tinuous extension northward of the special area from Tararu Creek to and beyond Rocky 
Point, at the latter locahty overlying the basement stratified rocks. Within the special area 
the lavas and breccias of the Tararu section are in the main greenish-grey rocks, consisting 
m.ostly of hornblende-pjToxene andesites and dacites. They exhibit en masse a very general 
chloritic alteration, and, as usual, in the vicinity of the veins are highly propyUtised and much 
lighter in colour than nonnally. The bieccias are well consoUdated. Only when they contain 
intercalated thin layers of fine tuff or ash. as they do m Ohio Creek, in the Sylvia low level, 
and in a few other places, is their disposition very evident. They are then seen to dip at low 
angles to the south-south-eastward. 

Southward of Tararu Creek, to within a few chains of Shotover Creek, Kuranui, the complex 
affords similar rocks — in some localities lavas, in others breccias predominating — all with the 
same general disposition. Towards the Shellback and Kuranui, however, propyUtisation is 
more general, and neither the original character nor the disposition of the rocks is so evident. 
Mention will be made later of certain breccia and ash beds containing seams of carbonaceous 
material which are exposed in the adit level of the Bonanza Claim just northward of Shellback 
Creek. These fvagmentals dip northward, and are possibly of later origin than the main mass 
of the complex. 

Continuing southward, associated flows and breccias which are undoubtedly of the Tararu 
Creek type have been penetrated in the Kuranui-Caledonian bore from a depth of 80 ft. to 
a depth of, say, 1,170 ft. (the horizon of the basement-rocks). The complex must, therefore, 
be considered to imderlie at least a portion of the non-brecciated andesites (b) to be later 
described. 

Hillward of the section described, hard greenish-grey breccias, of the Tararu Creek type, 
outcrop a few chains north-eastward of Alburnia shaft. 



69 

The ("ollarboiie fault, treudiug from Alhui'iiia Hill to the foot of Collarbone Creek and 
a somewhat arbitrary line extending from the latter point through Waiokaraka Gully and 
passing just north of the Exchange shaft of the Saxon Mine, separates on this side, at shallow 
horizons, the flow and breccia complex (a) from the uon-brecciated formation (6). The former 
lies to the east and south, the latter to the west and north. 

From the flow and breccia complex of the watershed of Karaka Creek and the northern 
side of Hape Creek, from the Una Hill area, and from the May Queen and Deep Sinker (Short- 
land Flat) claims on the foreshore, numerous rock-sections have been cut and examined. 
The chief varieties named in order of abundance are pjToxene-andesite, hornblende-pyroxene- 
andesite, hypersthone-andesite, and hornblende-andesite. With the andesites are associated 
dacites, carrying ferro-magnesian silicates similar to those in the andesites. Propylitisation 
of all these rocks is extensive, especially in the \'icimty of the various reefs, but masses of hard 
little-altered rock are of common occiurence. 

The flows and breccias of Karaka and Hape creeks in places show a general similarity 
to those of the Tararu Creek area. It is probable that certain beds of the former locahties 
are the upper portions of the Tararu Creek formation, but the relationship is by no means 
evident. Field evidence has led the writer to the conclusion that much, if not all, of the 
visible rock complex of the Una Hill and the lower portions of Hape and Karaka creek valleys 
have been extruded from a crater situated on the low grounds probably between Waiokaraka 
Creek and the mouth of Hape Creek. 

The ash-beds and the lava-streams of the Una Hill - Hape Creek area, of the Karaka- 
Collarbone spur, and of the isolated capping penetrated in the Bonanza Company's adit (Shell- 
back Creek) show quaquaversal arrangement (a dip from a common centre), the centre appa- 
rently being the old volcanic vent postulated. 

It is interesting here to note that McKay in a comparatively recent memorandum* specu- 
lated as to the existence of an old volcanic vent " situated three-quarters of a mile west of 
the shore of the Firth of Thames, opposite the town of Shortland, or the mouth of Karaka 
Creek." Again, Park, in 19U8t postulated the existence of what he termed the Waiokaraka 
volcano in or near the vicinity described by the writer. 

(6.) Non-brecciated Andesitc (the " Premier " flow). — Lying within the almost encircUng 
area covered by the flow and breccia complex described is an area, measuring about 480 
acres, in which no brecciated rocks are visible. 

The predominating rock here is a micropoeciUtic pyroxene-andesite in which a little 
hornblende is occasionally visible (for chemical analysis of the same see (4) p. 24). Hypers- 
thene and augite are generally present in almost equal proportions, but in certain sections 
either one or other of these minerals predominates. The hard andesite penetrated in the 
Trenton shaft, however, is rather more crystalline, and carries more hornblende than the usual 
type. The end of the straight course of the Moanataiari tuimel affords an interesting and 
rather uncommon variety which SoUas has determined as a " pyroxene-labradorite-holo- 
crystalhne rock — a phanerocrystalUne representative of pyroxene andesite."J 

As to whether the massive andesite of this fairly well-defined area represents a single 
heavy lava-flow exhibiting differentiation phases or more than one flow, with perhaps local 
intrusions, the evidence is by no means conclusive. It is very certain, however, that the 
direction of flowage in the greater bulk of the rock-mass is toward the south-west at fairly 
low or medium angles. The mass, therefore, appears to overlie the alternating flows and 
breccia-beds of the Tararu-Shotover Section. The possibihty of this being an inclined intru- 
sive sill or plug connected with the old " Waiokaraka " crater, lying just to the south-east- 
ward, was considered, but can hardly be maintained. 

* Mines Rec, vol. v, pp. 501-6. f M""- Joura., Aug., 1909 (London). J " Rocks of Cape Colville 
Peninsula," vol. ii, pp. 108, 109. 

Note. — Section.s cut and examined by the writer from the same locality show on comparison with section 
examined by SoUas a less crystalline structure. 



70 

Since the relatively heavy flow of p\Toxene-andesite has enclosed the quartz veins which 
have yielded all the great bonanzas of the Thames mining centre, and perhaps 85 per cent. 
of its total gold-silver output, it has in the subsequent pages of this report been designated 
the " Premier " andesite. 

Structural Breaks. — The area between the Shellback Creek - Alburnia Hill Une and Hape 
Creek is intersected by two well-marked structural breaks — the Moanataiari fault and the 
Beach " shde." From the former branches the Collarbone fault, a less definite hne of rock- 
fracture. All of these have been described before (see pp. .30-32), and their positions are 
indicated on the accompanying maps. 

The Moanataiari fault and the Beach " sUde " throughout the greater part of their courses 
are approximately parallel, and about 30 to 35 chains apart, and determine three separate 
blocks of country — the Upland block, the Central block, and the Seaward block. 

The Upland block is the extensive area lying to the foot-wall side of the Moanataiari 
fault. 

The Central block is that Ipng between the Moanataiari fault and the Beach " slide." 
The downthrow or vertical displacement of this block relative to the Upland block in the 
\acinity of Waiotahi Creek has been estimated at 600 ft. Further southward it gradually 
increases to, say, 1,000 ft. in the \'icimty of Una Hill. Northward from Waiotahi Creek its 
downthrow gradually decreases, the Moanataiari fault apparently forking in the vicinity of 
the Golden Era shaft (Kuranui). From this point a branch of the fault crosses the Shellback, 
and apparently strikes up Waitangi Gully ; another branch appears to strike seaward a Uttle 
to the south of Shellback Creek. 

The Seaward block is an unknown quantity both as regards the actual character of its 
consolidated rocks and the depth at which the sirrface of these rocks underlies the muds and 
gravels of the Firth of Thames. The results of boring operations suggest that the depth of 
the alluvium exceeds 1,120 ft. 

The Gold-hearing Reefs. — This special area of the Thames Goldfield is traversed by a large 
number of more or less distinct reef systems, which exhibit an approximate paralleUsm, and 
pursue a general north-east - south-west course. The most marked exceptions to this uni- 
formity are ofEered by the Hague-Smith reef and the Moanataiari " cross-lode," which strike 
nearly transverse to the normal direction. Each reef-system contains one or more principal 
veins and several subsidiary branching veins. 

The prevailing dips of the various reefs from Tararu Creek to the vicinity of the Saxon 
shaft at the Town of Thames is to the north-westward, at angles varpng from about 40° to 
90° (verticahty), the lower angles being almost invariably characteristic of the stronger 
reefs. Passing southward from the Saxon No. 1 reef near the Saxon shaft, the prevaiUng 
dip is to the south-eastward at high angles, but a perusal of the plans will show certain 
exceptions. 

In the Upland block — i.e., on the foot-wall side of the Moanataiari fault — the principal 
reefs are the Sunbeam, with its branch the Watchman, the Dunedin, Sylvia, Waitangi, 
Dixon's (possibly same as the Waitangi), Sons of Freedom, Reuben Parr, Golden Age, Wai- 
otahi-Cambria, Moanataiari Cross, Nana, Adelaide, Moa, Duke's, Loyalty, Occidental, Gib- 
raltar, and Hague-Smith. 

In the Central block — i.e., on the seaward side of the fault — the reefs which have proved 
important are Barry's, Shotover (Hui^t's), All Nations, Moanataiari No. 9, Caledonia Nos. 1 
and 2, Waiotahi-Cambria, Mariner's, Prince Imperial No. 2, Saxon Nos. 1 and 2, Cardigan 
Nos. 1 and 2, May Quean No. 4, Nor' West, Queen of Beauty, Queen of the May, and Van- 
guard. 

Owing to the great dislocation caused by the Moanataiari fault, and the fact that little 
mining exploration has been accomplished in the belt of country Ipng immediately to the 




Mow \TAI \l!l I-'mi T (Sl.ILKK.NSIliKl) I'OO 1 - W A 1. 1. ) I. Mi) 11A1;K IIY DkNUUATIO.N . WaIOTAIII (JiKKK 

\'am.kv, Thamks. 



Bulletin Xo. 10.] 



[Face p. 70. 



71 

foot-wall side of the fault, it is difficult to correlate reefs on the seaward side with those on 
the upland side. There is httle doubt, however, that the Waiotahi-Cambria reef can be 
correlated on each side of the offset, and that the Caledonia No. 1 can be correlated with the 
Golden Age. The Mariner's reef veers round towards the Waiotahi-Cambria reef, and may 
not reach the hanging-wall side of the fault, owing to the existence of the belt of hard rock 
mentioned later. As regards the Prince Imperial, Saxon, Cardigan, and Queen of Beauty 
vein-systems, at least in the upper levels, it is doubtful if any of these on their north-easterly 
strike even reach the hanging-wall side of the fault. This is due to the existence of a relatively 
extensive belt of hard comparatively imaltered rock which extends from near the foot-wall 
of the Waiotahi-Cambria reef in the Waiotahi Claim, through the Trenton section of the New 
Moanataiari Claim, through the north-east section of the Saxon Claim, and into the May 
Queen Claim. In tliis hard country it is not unlikely that the vein fissures gradually lose 
strength, and finally terminate. 

As far as possible, the claims lying mostly or altogether on the upland side of the Moana- 
taiari fault are the first reviewed in the following descriptions, and subsequently those lying 
mostly or altogether on the seaward side. 

Day Dawn and Norfolk Claim (area, 159 acres 1 rood 19 perches). — The properties of the 
Day Dawn and Norfolk Mines (Limited), registered in England, are situated on the southern 
side of the lower part of Tararu Creek. They consist of the Day Dawn and Norfolk claims, 
and also a small section of freehold land upon which stands the company's mill. 

The claims were for many years prior to 1887 divided into smaller holdings, and were 
worked by local companies. Some of these companies drew considerable profits from the 
high-grade ores afforded by the outcrops and upper horizons of the veins. The fact that the 
Russell battery, which formerly stood in Tinker's Gully, comprised no less than sixty stamps 
suggests that the ore-tonnage handled was considerable. The gold-output of these earlier 
and profitable years is unfortunately not recorded. That of the last two decades is not 
inconsiderable, but the ore treated has been too low in grade to yield a profit. The available 
statistics read : — 

Tons. Oz. Value, 

aty of Dunedin Company (1890-6) 761 246 £ 

Day Dawn Gold-mining Company 

(1894-6) .. .. .. 79 87 

Norfolk Gold - mining Company 

(1888-96).. .. .. 3,363 1,538 



4,203 1,871 (say) 5,200 

Tararu Creek Gold-mines (Limited), 
and Day Dawn and Norfolk 
Mines (Limited) (registered in 
England) (1896-19U8) . . 42,245 21,030 41,384 



£46,584 

The claims are worked from several adits, the lowest of which — the battery level — enters 
40 ft. above high-water mark. This is a well-constructed adit commanding the battery- 
hoppers, and is of sufficient dimensions to permit of the haulage of the mine-cars by horses. 

The mill consists of two rock-breakers, thirty stamps (1,000 lb. each). Challenge ore-feeders, 
amalgamating-tables, six berdans, cyanide plant, assay office, and accessories. Water-power, 
supplemented when necessary by steam, is employed for milling purposes, and also for operating 
air-compressors supplying power for the rock-drills in the mine. The capacity of the mill is 
1,200 tons per month. 



72 

The country rock of the claims consists of andesitic and dacitic breccias and flows, all 
more or less propyUtised. These rocks show a very irregular disposition, but on the whole 
they probably dip to the southward at low angles. Underlying them at a depth of, say, 400 ft. 
below the battery level are, it may be inferred, the argilUtes or slaty shales and the associated 
" felsites," which outcrop at Rocky Point. Here, therefore, mining is being carried on nearer 
the old basement-rocks than at any other locality at Thames. 

The quartz veins of the property are probably more or less continuous branches of one 
system of rock fracturing or Assuring. The principal veins of the adjoining Watchman and 
Dixon's ConsoHdated claims, and probably the veins of the Sylvia Claim, are also to be corre- 
lated with the same system, although continuity cannot in all cases be proven. 

The principal gangue minerals of the unoxidized veinstone are quartz (predominant), 
rhodochrosite, calcite, pyrite, zinc-blende, chalcop}Trit«, and galena. Rhodochrosite, the 
carbonate of manganese, more than any other mineral, characterizes the primary ore, imparting 
to it a deUcate pinkish tinge. Rhodonite, the siUcate, which also gives the same colouration, 
may occasionally be present, as judged from analyses. The oxidation of rhodochrosite to the 
black incoherent oxides — wad, &c. — gives a black sooty appearance to much of the ore at and 
near the surface. 

As a general rule, it has been found in the mine that the veinstone containing the higher 
percentage of manganese-carbonates (the pinkish ore) carried the higher values in gold and 
silver. The following analyses of (1) a sample of rich ore, (2) a sample of rather low-grade 
ore, are of interest : — 

Sihca (SiOa) 
Alimiina (AljOg) 
Ferric oxide (FejOg) . . 
Iron-disulphide (FeSj) 
Lime (CaO) . . 
Magnesia (MgO) 
Manganous oxide (MnO) 
Carbonic anhydride (CO 2) 

100-00 100-00 

(1.) Gold, 14 oz. 7 dwt. 8 gr. per ton ; silver, 5 oz. 2 d\vt. 16 gr. per ton. 
(2.) Gold, 5 dwt. 1 gr. per ton ; silver, 3 dwt. 3 gr. per ton. 

Mining operations in this property have been principally confined to four different sec- 
tions, known respectively as the Simbeam, the Dunedin, the Day Da\vn, and the Norfolk. 
The only two of these sections actually connected by underground workings (a crosscut) are 
the Sunbeam and the Dunedin. In each of the four sections a different vein or branch of 
the vein-system has apparently been worked. 

The stoping-plans of the veins in the various sections show that while certain steeply 
pitching ore-shoots can be broadly recognised, the payable ore within the hmits of these shoots 
is rather patchy. A very considerable amount of ore, assaying about 12s. per ton, is said to 
exist ; but this is not remunerative under present conditions, and the locating of higher-grade 
ore involves considerable prospecting-work. The manager* informs the writer that a feature 
often noticeable in the various veins is the occurrence of a seam carrying high values, and 
varying in width from a hne to 12 in. This is generally found at or near the middle of the 
vein, and in such case a definite width of the enclosing veinstone is probably payable. Again, 
this seam may follow a serpentine course through the vein, when the whole width 
of the veinstone usually proves payable. The occurrence of faults, cross-courses, and inter- 
sections have also had a marked effect on the localisation of the pay-ore. 





(1.) 

78-25 


(2.) 
52-84 




1-89 


3-08 




2-18 


3-52 




0-51 


1-80 




2-65 


15-15 




0-30 


3-73 




8-02 


2-41 




6-20 


17-47 



* Mr. MacCormack. 



73 

It has been noticed on stoping certain veins that the pay-ore is disposed in gently incHned 
zones or floors, which alternate with zones of barren or low-grade veinstone. Two or three stopes 
may therefore yield good ore, and the next two or three much poorer ore. These zones are 
said to usually dip towards the south or south-west, and, as this is the probable disposition 
of the bedded volcanics, it would seem that certain beds have exercised a more potent influence 
than others on the precipitation of the precious metals. 

Sunbeam Section : In the Sunbeam Section the outcrop of the vein was located in the 
Sunbeam Gully, at an elevation of 470 ft. Here a great mass of quartz occurs, probably a 
junction of Sunbeam vein and at least two strong foot-wall branches or droppers. The outcrop 
and shallow workings on the junction afforded a considerable tonnage of payable ore, but 
in the intermediate blocks between these and the battery level the foot-wall branches, and 
particularly that known as No. 1 Foot-wall reef, have contributed the greater part of the ore 
mined. 

The main Sunbeam vein at the battery level, 450 ft. below the outcrop, is at least 12 ft. 
in width ; but the assays here and throughout the block extending upwards for 90 ft. seldom 
showed values exceeding 12s. per ton. At 100 ft. above the battery level an intermediate drive 
on this vein revealed ore varying from 14s. to £2 18s.; but exploration above this horizon has 
been conflned to the foot-wall branches rather than to the parent vein. The length of the 
blocks stoped in the Smibeam Section seldom exceed 300 ft., and are usually a good deal less. 

Dunedin Section : In the Dunedin Section, which has proved the most productive portion 
of the mine, the Dunedin reef ranges in width from 1 ft. to 15 ft., and possibly averages (5 ft. 
The blocks stoped between the Dunedin level and the outcrop, a vertical distance of 380 ft., in 
places exceed 550 ft. in length. A good deal of the vein still remains intact here, and parts 
of it are expected to prove payable. The further exploitation of the vein above the Dunedin 
level and northward of the blocks stoped is contemplated. So also is the opening-up of the 
block extending from the Dunedin level down to the battery level. These levels are vertically 
118 ft. apart, and are connected by rises. 

A fault or cross-course dipping southward at high angles appears to have determined 
the northward Hmit of the stopes on the Dunedin reef, and beyond this little or no prospecting 
has been done. 

Day Dawn Section : In this section the principal vein — the Day Dawn — varies in width 
from 2 ft. to 6 ft., and has been worked from three adits, the lowest of these being 255 ft. 
above the battery level. The length of the stoping-blocks approximated 250 ft., so that the 
vein has evidently yielded a good deal of ore. A winze being sunk from the lowest or Day 
Dawn level is aftording encouraging prospects. 

Norfolk Section : The Star of California reef, which ranges in width from 1 ft. to 8 ft., 
yielded the greater part of the ore won from this section of the mine. Gold to the value of 
£10,000 is stated to have been extracted from the blocks between the No. 3 level and the surface 
prior to the year 1895. Below this the vein has been driven on over 1,000 ft. in the Wild 
Missouri level (176 ft. above the battery level), but the main ore-shoot measures -.n the slope- 
length here, as in the upper levels, about 2(KJ ft. to 250 ft. 

Although the Day Dawn and Norfolk Mine has been worked for the last forty years, 
relatively large areas still exist in which little or no prospecting has been done. It would 
appear that the company's chances of success depend largely on the discovery of further ore- 
bodies in these unprospected areas. Recent developments in the adjoining Watchman Mine 
point to the advisability of systematically prospecting the large block lying between the Sun- 
beam, Dunedin, and Watchman workings. In this block the Sunbeam vein and its strong 
foot-wall branches, including that worked in the Watchman, should exist. It is further pro- 
bable that the junction of the Dunedin reef with the Sunbeam would here be located, and 
such intersections are not infrequently productive of pay-ores. The exploitation of the Star 
of California and Day Dawn veins from the Dunedin level, which will aflford 70 ft. and 140 ft. 



74 

of backs respectively, is now under consideration by the management. The battery adit, it 
may be remarked, is a valuable asset to this company, since it commands a considerable 
extent of the Tararu Creek country both within and beyond the hmits of the Day Dawn and 
Norfolk Claim. 

Watchman Claim (area, 88 acres 2 roods ; owners. Watchman Gold-mining Company, 
Auckland). — The workings of the Watchman Claim, which adjoins the Day Dawn and Norfolk, 
are situated in the Sunbeam Gully, at an elevation of about 700 ft. 

Andesite flows and breccias (propylitised), similar to those of the lower Tararu Valley, 
constitute the enclosing rock of the veins. 

The gold-output of the area covered by this claim has in the past proved very small, 
since the outcropping portion of the veins proved unremunerative, and only recently has 
systematic prospecting at deeper levels been imdertaken. The claim has recently come into 
prominence owing to the encouraging prospects met with in these deeper workings. 

Minerahsation in the Watchman is in general similar to that in the Day Dawn and Norfolk 
area. Pyrite, galena, zinc-blende, and copper-pyrites are the sulphides usually associated with 
the vein-quartz. The pinkish rhodochrosite ore is noticeable only in places, but may be expected 
to increase in quantity with depth. The sulphides generally occur in small dark isolated patches 
and specks throughout the white finely crystalline quartz, but occasionally, as in the Silver 
Crown vein, they form definite bands in the ore. 

The free gold, when visible in the ore, is almost invariably associated with the darker 
sulphide patches. Sulphide of silver is occasionally present as a dark bluish-grey finely granular 
mineral. The analyses of a sample of concentrates derived from ore collected from the dumps 
showed no trace of tellurium. 

Most of the vein-material, especially that of the principal vein, exhibits the effects of 
crush owing to movement of the wall-rocks, and as the claim is water-free, owing to the proximity 
of the deeper workings of the Day Dawn and Norfolk, this much-iointed and crushed ore 
admits of being cheaply mined. 

A good deal of the veinstone is peculiarly honeycombed and cavernous, and is suggestive 
of the effects of leaching. The rhodochrosite ore when encountered is, in contrast, particularly 
hard and compact. It would appear that at present levels leaching has been in excess of 
secondary deposition or enrichment, although a few lenses and streaks of dark crumbling 
high-grade sulphide ore — probably secondary — are noticeable in the crushed veinstone. 

The principal vein of the area is the Windfall or Watchman, with a general north-easterly 
strike, and a dip to the north-westward at angles averaging 37°. Its total width varies from, 
say, 5 ft. to 20 ft., with strength well maintained at the lower levels. A clay selvage or 
band of pug about a foot thick — further evidence of rock-movement — persistently follows 
the hanging-wall from the highest to the lowest level. Ribs of country rock are not 
uncommon within the veinstone, and some of these are in mining apt to be mistaken for 
the actual wall-rock. Several branch veins or independent veins have been located in the 
foot-wall country of the Windfall, but the extent of the prospecting done on these so far is 
rather limited. 

The Windfall is probably a foot-wall branch of the Sunbeam reef of the Day Dawn and 
Norfolk area, but only further underground exploration will definitely estabUsh its identity. 
The actual limits of the ore-shoot now being prospected have, the writer understands, not 
yet been determined. A winze has been sunk on the vein from the lowest adit level to a 
depth of 145 ft. measured on the incline, and the ore exposed down to this point is payable, 
and has occasionally yielded a few pounds of picked stone. 

If development-work on this Windfall shoot discloses a considerable tonnage of pay- 
ore, profitable exploitation depends largely upon the scheme to be adopted for its mining, 
transit, and milling. In this connection it may be suggested that a satisfactory flrrangoment 



75 

between the Watchman Company and the Day Dawn and Norfolk Company would be 
certainly advisable. That large bodies of vein-quartz exist in the Sunbeam and Day Dawn 
sections and in the Watchman area is undoubted. The discovery of ore-shoots in addition 
to that located in the Windfall reef would thor*!fore not be unexpected as the result of co- 
operation and systematic prospecting. 

Dixon's Consolidated Claim (area, 97 acres). — The Dixon's Consolidated Claim, which 
is being worked by the Dixon's ConsoUdated Company (Auckland), adjoins both the Day 
Dawn and Norfolk and the Watchman areas, and shows similar geological formations. 

Mining operations arc of a purely prospecting character, and are principally centred on 
the north-easterly extension of the Windfall (Watchman) reef. 

The vein at its outcrop shows a width of about 18 ft. and a dip of 34°, and is, as in places in 
the Watchman property, separated by a sheet of propylite into two portions. It has recently 
been intersected at a depth of 250 ft. below its outcrop by an extension of the Day Dawn level, 
but so far the limited amount of prospecting-work done has not disclosed an ore-shoot. 

Sylvia Claim (area, 264 acres rood 16 perches). — The Sylvia Claim is situated in the 
Tararu Crock Valley, and more particularly within the watershed of the Ohio branch. The 
elevation of the lowest adit level is 434 ft. above high-water mark. 

The property is now owned by the New Sylvia Gold-mining Company, of Auckland. 
From 1890 to 1893 it was worked by the Sylvia Gold-mining Company, of Melbourne, and 
prior to that by private individuals and small companies. The gold-silver output of tiie 
earlier years is not recorded, but the following figures appear in the Mines Reports, or have 
been quoted by piovious writer:? : — 

Taylor and Sons, from portion of claim known as Little Agnes £ 

(about 1877), sold to one of the banks 2,695 oz. bullion, 
valued at . . . . . . . . . . . . 6,587 

The Sylvia Gold-mining Company, Melbourne, mined and milled 
from 1890 to 1893 6,500 tons of ore for bullion representing 
a value of . . . . . . . . . . . . 16,266 

The Kaiser Gold-mining Company, raised from a portion of 

Sylvia (1896 99), 126 tons which yielded . . . . 320 



£23,173 

In addition to the above, certain concentrates left on the battery-site by the Sylvia 
Company wore subsequently shipped to smelters for a highly profitable return, which has not 
been recorded. 

The rocks of the area are propylitised andesites, both brecciatod and massive, with a few 
remnants—" bars " — showing comparatively little alteration. Those volcanics exhibit an 
irregular stratification, with a general dip to the south-south-eastward at low angles. The 
rocks are much jointed and crushed, and many of the underground excavations require 
considerable timbering, particularly if percolating water is present. 

The reef-system of the Sylvia is on the whole decidedly broken. In addition to the veins 
exploited, several outcrops, probably referable to parallel or branching reefs, have been located, 
and the whole may be a north-easterly extension of the Day Dawn and Norfolk system ; but 
actual correlation is at present impossible. The area shows evidence of con.siderable faulting, 
although no very definite post-mineral dislocations are apparent. 

The principal vein, and the one now being exploited, is known as the Sylvia or Little 
Agnes ; but several others, among which are the Kaiser and Iron Cap, were worked in a small 
way in the earlier days. 



76 

The Sylvia vein strikes in general about N. 70° E., and, dips either in one direction or the 
other, or is vertical, thus exhibiting the form of a warped fissure. Its width varies from 1 ft. 
to 8 ft., and will probably average about 5 ft. The vein in the No. 3 adit tevel has been 
driven on for 1,020 ft. In the south-western end of these workings the vein fissure appears to 
have weakened or feathered out, and, although some 350 ft. of driving and crosscutting has 
been done here, its further continuity has not been estabUshod. The No. 4, or lowest adit 
(114 ft. below No. 3), was projected in a straight line a distance of 1,695 ft., and intersected 
the vein about the middle of the ore-shoot. Driving in each direction on the vein is in pro- 
gress, and a rise connection has been made with the level above. 

The ore-shoot of the Sylvia vein has in No. 3 level a broken!}- continuous stope-length 
approximating 500 ft., and the block has been worked upwards from this level to the outcrop, 
a vertical height of about 240 ft. At No. 4 level the length of the shoot has not yet been 
determined, but it will probably measure about the same as in the shallower levels. It may 
be stated that not all the vein-material occurring within the limits of the shoot affords payable 
ore. Both in rising and in driving patches are found within the fissure, which consist of httle 
else than crushed rock with occasionally a few small bunches or stringers of veinstone. On this 
account, any estimates of ore-reserves are only possible after development-work is well 
forward, and even then the figures obtained must be regarded as only approximate. 

It should be remembered that this vein intersects at high angles propyhtised beds of 
tufaceous and flow andesite, which are disposed generally at low angles. In the No. 3 level, 
as far as could be observed, an altered heav}' band of flow rock existed, and afforded fairly 
uniform ground. In the No. 4 level, however, alternating beds of varying character are con- 
spicuous ; some even show an admixture of carbonaceous material. As the tenor of an ore is 
frequently found to vary with the nature of the wall-rocks, it is not unlikely that below and 
probably above No. 4 level fairly horizontal alternating floors or zones of higher and lower 
grade veinstone will be encountered. 

The ore of the Sylvia vein is decidedly complex. With the milky-white or bluish-white 
finely crystalline quartz, which frequently shows cavernous and " sugary " structures, is 
associated a considerable amount of zinc-blende, galena, p}Tite, and chalcopyrite. Bornite, 
malachite, and other cupriferous minerals derived from the chalcopyrite are also sparingly 
present ; while the amethystene colouration, indicating the presence of the carbonate or the 
siHcate of manganese, is occasionally noticeable. Highly mineralised samples collected by the 
writer yielded on analysis no trace of tellurium. Free gold is occasionally visible in the ore, 
and generally occurs in quartz near the contact of the sulphide bands. The zinc-blende, 
galena, and chalcopjnite are frequently associated, and form interlacing ribs in the quartzose 
gangue, or nodules and bunches in the softer crushed veinstone. Crustification is con- 
spicuous in most of these ribs and nodules — that is, there has been a tendency to successive 
deposition of the individual sulphides at least in the later period of vcin-fonnation. On the 
whole, the order of deposition of the three commonly associated sulphides is — (1) zinc-blende, 
(2) galena, (3) chalcopyrite ; but occasionally contemporaneous deposition of all the sulphides 
appears to have supervened. 

Separation of the various sulphides has shown that the galena usually carries the higher 
values in gold and in silver ; but both the zinc-blende and the copper-pyrites are frequently 
rich in the precious metals. According to one of the mine reports, assays of clean galena 
5delded 49 oz. of gold and 177 oz. of silver per ton ; and in the case of zinc-blende ore, 26 oz. of 
gold and 87 oz. of silver per ton. It is noticeable that the proportion of silver to gold in the 
galena is very Uttle higher than in the zinc-blende. 

Pyrite as definite bands or conspicuous aggregates is uncommon ; the mineral generally 
occurs as well-formed small cubes more or less isolated in association with the other sulphides, 
and in a finer state of division throughout the whole of the quartzose gangue and the wall- 
rocks. 



77 

The sum total of the sulphides constitutes between 8 per cent, and 10 per cent, of the 
weight of the bulk ore. 

The following particulars, culled from the reports* of Dr. A. Scheidel, managing director 
and metallurgist of the Sylvia Gold-mining Company in 1891-3, are submitted : " The plant 
(now remov(^) consisted of ten stamps, amalgamating-tables, four classifying-boxes acting 
as separators of the slimes from the coarse material, six jiggers for concentrating the coarse 
sand, two large tanks for settling the slimes, twelve rotary tables for concentrating the slimes, 
and three buddies for the final cleaning-up of the whole of the tailings." 

To the above crushing, amalgamating, and concentrating mill, a small cyanide plant was 
subsequently added for the extraction of the gold and silver from the concentrates. 

The following gives an outline of the results of treatment reported for the first year's 
operations : " The value of the crushing-dirt varied considerably ; the greater bulk assayed 
before treatment between £3 and £i per ton (for gold-silver) ; a considerable tonnage reached 
as high as £10 per ton ; at other times very low-grade stuff had to be handled." 

" 5,.300 tons of ore ^.neldod 440 tons of concentrates, valued at £12,033. The free gold- 
silver bullion saved on the plates amounted to 1,278 oz., valued at £3 12s. per oz. — £4,629 — 
(17s. 5d. per ton of ore). The concentrates saved therefore amounted to 8-3 per cent., and 
carried values representing £2 5s. 5d. per ton of the crude ore. The tailings going to waste 
varied between 9s. and 15s. per ton, and occasionally showed higher values. The total value 
saved per ton of crushing-dirt amounted, between concentrates and free gold, to £2 9s. 8d. ; 
the average value saved of the assay value per ton of ore being estimated at 80 per cent." 

As the results of the treatment of 341 tons of concentrates by agitation with potassium- 
cyanide solution the average extraction is stated to have amounted to 82-67 per cent, of assay 
value. 

The cost of crushing, amalgamation, and concentration is stated at the low figure of 
38. 6d. per ton. The power employed, it may be remaikod, was hydraulic. 

In briefly commenting upon the important subject of the treatment of the Sylvia ore it 
may be stated that Dr. Scheidel's investigations suggest that crushing followed by amalga- 
tion and efficient concentration should form part of any system of treatment to be adopted by 
the present company. Since the year 1893, concentration methods have made considerable 
advancement, and it would appear to the writer that the concentration processes now being 
worked with very considerable success on the zinc-galena ores of Broken Hill, Australia, should 
here be given due consideration. 

The fact that the galena-zinc-copper content of the Sylvia ore is quite considerable 
renders it probable that the shipment of the classified concentrates to smelters, rather than 
their local treatment by the cyanide process for gold and silver alone, will be found advis-ablc. 

As regards the quartzose sands, the cyanide tests carried out by Scheidel indicate that 
they can be economically treated by cyaniding. 

The ore-shoot of the Sylvia promises to yield a considerable amount of payable ore, both 
above and below the present low level. This adit, which is 434 ft. above sea-level, affords 
114 ft. of backs, and necessitated the driving of a crosscut 1,695 ft. in length. As the opening- 
up of further blocks from adit-workings would involve much more lengthy crosscuts it is pro- 
bable that a shaft will be sunk to further exploit the ore-shoot. The Day Dawn and Norfolk 
Company s battery level, which would afford some 330 ft. of backs, has its present terminus, 
unfortunately, 4,000 ft. from the Sylvia ore-shoot, and its extension is therefore not likely 
to be regarded with favour. 

Bonanza Claim. — The Bonanza Claim (area, 89 acres 1 rood 20 perches) is owned and 
worked by the Bonanza Gold-mining Company, of Auckland. It is situated on the foot- 
hills between Shellback and Sunbeam creeks, and is bounded on the one side by the Thames- 

• C.-4, 1891, pp. 28-30 ; C.-3, 1892, pp. 37-40. 



78 

Tararu foreshore and on the other sides by the Day Dawn and Norfolk, the Watchman, the 
Waitangi, and the Kuranui mining-claims. 

The area within the boundaries of this claim has yielded little or no gold, and, in fact, 
has received Uttle attention prior to the present company taking it up some two or three 
years ago. 

The rocks of the area are irregularly bedded tufaceous and flow andesites, all more or 
less propyhtised. 

Several quartz veins, concerning which Uttle is known, outcrop within the claim- 
boundaries, but up to the time of the writer's examination of the property work was confined 
to driving a prospecting crosscut in a north-north-easterly direction at an elevation of 236 ft. 
in Shellback Valley, with the object of intersecting the continuation of the main reef worked 
in the adjoining Waitangi Mine. Two or three quartz veins ha\-ing different strikes to the 
one sought were cut and followed for some distance, but were found to carry only negUgible 
values in gold and silver. The Waitangi vein was not located, and, if the writer's interpreta- 
tion of conditions in the Waitangi Mine is correct, is never likely to be located within the 
Bonanza ground. 

The highest assay obtained from four samples of veinstone collected by the writer was 
that from a 2 ft. vein exposed in the track-cutting a chain or so below the mouth of the pro- 
specting- drive. This yielded 1 dwt. of gold and 8| dwt. of silver per ton (value, 5s.). 

Attention is now confined to prospecting operations in the northern end of the claim, 
where the south-westerly extension of one of the veins of the Day Dawn and Norfolk property 
is reported to have been located. 

Waitangi Claim. — The Waitangi Claim (area, 62 acres 1 rood 28 perches) is situated on 
the northern slopes of the valley of Shellback Creek, and is bounded by the Bonanza, Watch- 
man, Dixon's ConsoUdated, Old Alburnia, and Kuranui claims. The property is owned and 
worked by the Waitangi Gold-mining Company of Auckland, formed in 1906, but prior to this 
date it received very httle attention at the hands of the miner. The main reef was in the 
early days cut in a level known as the Siam, now incorporated in the present workings ; and 
some gold was won from the upper portion of the vein. Possibly the refractory nature of 
the uuoxidized ore subsequently encountered led to the cessation of these earlier mining opera- 
tions. The present company, in 1907 and 1908, treated 41 tons of ore for gold-silver bullion, 
valued at £610. 

The rocks of the claim as a whole are the more or less altered andesitic flow and breccia 
complex. The actual mine-workings, however, seem to be confined to one of the heavier 
bands of massive or flow andesite forming part of this complex, and is of the character usually 
regarded as favourable country. 

The mine-workings are confined to one large vein and one or two small subsidiary veins. 
The disposition of these is indicated on the accompanying plan. The absolute identity of the 
principal vein is unknown, but it is probably the westerly continuation of Dixon's No. 1 reef 
of the old Alburnia property. As the plan and the following sketch will show, this Waitangi 
vein, which has normally an almost east- west strike, turns abruptly in the western end of the 
workings, and assumes nearly a north-south course. A pug-filled fissure, however, which 
throughout the whole of the workings on the east-west strike of the vein persistently follows 
the hanging- wall, departs from the vein quartz at this bend, and pursues its normal westerly 
course. The conditions obtaining at and west of this bend have given rise to considerable 
speculation both by those interested in the Waitangi property and by those connected with the 
adjoining Bonanza Claim, in which ground the westerly extension of this large vein was sought. 
In the writer's opinion, the main branch of the Moanataiari fault crosses the Shellback Creek 
some distance below the waterfall, and strikes up the gully of the small stream entering on 
the north side just below the Waitangi low level. It is the existence or proximity of this fault 
that has given rise to the conditions observed in the westerly workings of the Waitangi Claim. 



79 



The north-south " leg " of the main reef appears to be due to minerahsation having followed 
a fracture subsidiary and nearly parallel to the fault-plane ; this veinstone, however, is 
continuous round the elbow or bend with that of the east-west " leg " of the reef — the older 
Dixon's (?) hne of fracture. The actual length of heave or offset of the Dixon's (?) Hne of reef is 
difficult to determine. If it approaches 600 ft. — the calculated downthrow of the Moanataiari 
fault further southward — then one of the large rather poorly defined veins showing in the 
northern portion of the Kuranui Claim represents the seaward extension of the Dixon's or 
Waitangi line of reef. If the influence of the Moanataiari fault is held to account for the 
peculiar bend in the reef (mineralisation extends along part of the line of offset), it implies 
that the formation of the Moanataiari fault fissure, though not necessarily the last down- 
throw along the fault, antedated, in part at least, the mineralisation of the Waitangi vein. 
Other evidence in the Thames area, such as the conspicuous bulging-out and complex forking 
of the Waiotahi-Cambria reef near the main fault in the old Cambria workings, supports this 
theory. 




Sketch of Waitangi Vein 
showing bend and approx- 
-imate positron of bmnch 
of Moanataiari fault 



Three adit levels give access to the workings of the Waitangi Claim — No. 1, 248 ft. above 
sea-level ; No. 2 (Siam), 122 ft. above No. 1 ; No. 3, 116 ft. above No. 2. 

The main reef has throughout the three levels, on its east-west trend, an average dip of 
50° to the northward. The actual width of the veinstone on the east-west trend of the 
reef in the No. 3 or top level is 5 ft. 6 in. ; in the No. 2 or mid-level, 15 ft. to 20 ft. ; at the 
No. 1 or low level, 12 ft. to 23 ft. 

The reef is confined to lines of fracture along which considerable shearing has taken 
place. Sohd compact veinstone is rarely found continuous from one wall to the other in 
any cross-section. As the position of the drifts will suggest, the most promising-looking and 
solidest band of quartz occurs in general on the hanging-wall side of the reef. Other bands 
occur in places on the foot-wall side or in the median parts. Much of the vein formation, 
however, especially in the middle portion, consists of jointed and crushed country rock, more 
or less siUcified. Throughout this replacement material, bunches, lenses, and parallel stringers 
of harder veinstone occur at intervals. 



80 



The mineralisation of the ore-shoot of the Waitangi vein is of considerable interest, and 
presents features quite uncommon to the Thames area. In addition to the generally dis- 
seminated pyrite, the sulphides, galena, zinc-blende, and copper- pyrites occur in bands, streaks, 
and bunches in the quartzose gangue. With these is found in places a steel-grey lustrous 
telluride mineral, which proves to be mainly hessite, \vith in places a little tetradjnnite. Free 
gold is generally noticeable in association wnth this telluride mineral, and again occurs in the 
white quartz — usually in a fairly fine state of division, yet in sufficient quantity occasionally to 
afford " specimen stone." Barite is occasionally found in vugs as a secondary mineral encrust- 
ing dark granular pyrite. The following analysis of a sample of concentrates obtained by 
crushing and panning some of the richer high-grade sulpho-telluride dump ore is of interest : — 



SiUca (SiOa) 

Lead 

Iron 

Zinc 

Copper 

Sulphur 

Tellurium 

Silver 

Moisture and imdetermined 







Per Cen 




.. 12-95 






18-03 






10-64 






20-07 






7-93 






24-48 






1-80 






2-88 






1-22 



100-00 



Total .. 

No bismuth was present in this sample. 

Assay : Gold, 29 oz. 18 dwt. 14 gr. per ton ; silver, 932 oz. 3 dvrt. 6 gr. per ton. 

The proportion of concentrates that the general run of the ore of the pay-shoot would 
yield has not been ascertained, but it would probably amount to 8 per cent, or 10 per cent. 

The zinc-blende and copper-pyrites are almost always associated in the parallel bands, 
ramifying veinlets, and irregular bunches. Kernels of quartz or countrj' rock are not infre- 
quently enclosed by concentric bands of these associated sulphides. A general but not a S}'m- 
metrical crustification is apparent, and appears to have been due to deposition in parallel and 
intersecting fissures, which were reopened from time to time. No definite order of deposition 
of these sulphide minerals is apparent. Zinc-blende occasionally occurs alone as resinous scales 
exhibiting some alignment, in bands of bluish-white quartz ; such bands, it may be remarked, 
generally carry very fair values in gold and silver. 

Of the telluride ores, hessite, the telluride of silver, which usually contains a variable 
amount of gold, is certainly the principal mineral. To the unaided eye this telluride appears 
as a fine-grained steel-grey mineral exhibiting irmumerable small flashing facets. Under the 
lens the hessite is observed to be intimately associated with small crystals and blebs of vitreous 
quartz, the whole forming a very fine-giained aggregate. The telluride mineral of this ore 
has not infrequently been mistaken for finely granular galena. Several specimens examined 
under the microscope show unmistakably that most if not all of the high-coloured free gold 
which is frequently associated with the telluride is secondary, and has been precipitated on the 
telluride mineral. That tellurides have the property of precipitating gold from acid solutions 
has frequently been demonstrated in laboratory experiments. (For other occurrences of 
tellurides in Hauraki, see p. 38.) 

The principal ore-shoot of the Waitangi Mine is confined to the vicinity of the marked 
bend in the vein, and, judging from the stoping operations in progress above the low level 
(No. 1), the stope-length of the shoot is short. The pay-ore is furthermore apparently con- 
fined to the hanging-wall side of the vein, where, as mentioned before, the most compact and 
solid veinstone occurs. A prospecting-drive was at No. 1 level carried along the foot-wall 




SlIKI.I.H.M K CltKKK V.M.I.KY, TuAMKS 



Siiowim: I,o(ai,iiy or iiii: \V.\riAN<;i (Ioi.d-mimm; ('(^\l^A^■Y's 
\V(HiKixi;s. 



Hull (tin X<>. 10.'] 



l-'an ji. Sil. 



81 

in the vicinity of the ore-shoot, but lierc the gold-silver values were very low, and stojiini; 
operations are at present not concerned with this side of the vein. 

A rise has been carried throuoh from the No. 1 or low level to the No. 2 level. This opens 
from the hanging-wall side of the vein at the bend, but in its upper portion is altogether in the 
hanging-wall country rock. The dip of the vein, together with its almost right-angled turn in 
strike, gives rise to a structure in this stoping-block resembling the edge of a pyi-amid. A winze 
has been sunk from the low level for a few feet (as far as the ground-water would allow), and 
the results obtained here are repoi-ted to have been satisfactory. Ribs showing tellurides 
and free gold were encountered ; and it is stated, as the result of observations made in stoping 
and sinking, that the amount of telluride ore is increasing as depth is attained. The pitch 
of this pay-shoot will probably depend altogether on the position of the bend in the vein. 

Beyond the limits of the ore-shoot described, the average tenor of the \einstone exposed 
is low, even in the hanging-wall portion, which may be generally considered the best. In the 
extreme eastern end of the workings at the No. 2 level, however, a crosscut which exposes 
the whole vein-formation — some 20 ft. in width — shows some promising-looking ore. particularly 
in the foot-wall section. Average values ranging from £2 to £3 per ton over portion of this 
cross-section liave been indicated by assays. The vein on the corresponding section of th*; 
low level is somewhat disturbed by transverse faults. The further advancement cf the drifts 
in this end of the workings seems advisable. 

In addition to the main Waitangi reef, a fissuie formation known as the Siam reef and a 
small cross-vein connecting the Waitangi and Siam have been worked. The Siam leef is from 
4 ft. to 7 ft. in width, but its filling consists of pug and crushed rock with occasionally ribs 
and bunches of quartz. It has proved non-productive, and may be regarded as a fault rather 
than a vein. The cross-leader, which at the No. 1 level has a length of about 60 ft., and varies 
from 2 in. to 12 in. in width, exhibits similar mineralisation to the main reef, and has yielded 
a limited amount of payable ore. 

Apart from any discoveries which further prospecting beyond the eastern end of the present 
workings may reveal, the future prospects of the claim depend eutiroly upon the results which 
may attend exploitation below the existing low level (elevation, 248 ft.). Present indica- 
tions and the character of the mineralisation certainly appear favourable to the further per- 
sistence of the main ore-shoot in depth. An adit to command the maximum backs (say, 210 ft.) 
would not be less than 1,850 ft. in length by the straightest line from the foreshore. 

The metallurgical treatment of the sulpho-telluride ore of the Waitangi has been presenting 
considerable difficulty. The methods adopted in Cripple Creek (U.S.A.), Kalgoorlie (Western 
Australia), and (jther goldfields where tellurides of gold and silver occur under various con- 
ditions, should, however, be a sufficient guide to the most economical treatment of this class 
of ore at Thames. 

Old Albumin Claim (area. 181 acres 2 roods 22 perches ; owners, the Old Alburnia Gold- 
mining Company, Auckland). — This claim fovers a large irregularly .shaped area lying mostly 
within the watershed of the Moanataiari Creek, but in places extending northward into the 
watersheds of the Shellback and Tararu creeks and southward into the watershed of Waiotahi 
Creek. Adjoining claims are the New Moanataiari, Moanataiari Extended, Waitangi, Dixon's 
Consolidated, Magnet, Reliance, Thames, and West Coast. 

Numerous adits give access to the extensive underground workings of the upper levels, 
and certain of these are connected by a shaft 600 ft. in depth sunk from the top of a hill (collar- 
elevation of 1,170 ft.). This shaft appears to have been sunk so that the ore could be raised 
to a sufficient height to admit of aerial transit. Recently the Moanataiari tunnel has been 
extended to a point 97^ chains from its entrance, and here a rise has been constructed to connect 
with the Sons of Freedom level — the lowest main adit of the upper workings at 480 ft. higher 
elevation. 

6— Thames. 



Tom. 


Oz. 


vaiuts. 

£ 


18,866 


19,903 

1 


52,755 


444 


260 




549 


823 




3,535 


2,297 




1,170 


784 


1- 18,645 


10,011 


2.513 




82 


40 




132 


147 




446 


172 





82 

The recorded, gold-i'eturns from this property only refer to comparatively recent years, 
when the upper levels of the claim had been largely depleted of their pay-ores. They are as 
follows : — 

Now Alburnia and Old Allmrnia com- 
panies (1887-1908) 

Freedom Gold - mining Company 
(1890-96) 

Whau Gold-mining Company (1899-90) 

New Whau Gold - raining Company 
(1891-1901) 

Dixon's No. 1 Syndicate (1888-90) . . 

Dixon's Extended Sjoidicate (1890-94) 

Flying Ckmd Syndicate (1891-92) . . 

Nordenfeldt Syndicate (.John o' Groats), 
(1890-94) 

Coliban (1888-95) . . 

35,235 26,939 £71.400 

The companies that exploited the original Alburnia Claim, which forms but a part of 
the present holding, are statedf to have paid in dividends between the years 1868 and 1888 
the sum of £72,500. In the year 1893 a further sum of £7,500 was distributed among share- 
holders from the same claim. The name of the Old Whau Company, which formerly worked 
a part of the present Alburnia Claim, also appears in the listsj prior to 1887, with a profit- 
distribution of £11,650. The recorded dividends therefore total £91,650. The figures quoted 
suggest that the value of the total output from this section of the claim exceeded £300,000. 

Another formerly productive block of groimd now included within this company's holding 
is that situated in the Messenger's Hill locality, and generally known as the Point Russell or 
Reuben Parr. There is no record of the considerable gold-returns of the early days from 
this block ; and the reduced output of more recent years was incorporated with the returns 
of the New Moauataiari Company, which owned and worked the Reuben Parr in conjunction 
with a large adjoining area. It can, at least, be affirmed that this locality has proved, with 
the exception of the original Alburnia Section, the richest ground at Thames on the foot-wall or 
upland side of the Moanataiari fault. 

The country rock of the Old Alburnia Claim, forming the zone in which the veins yielded 
payable ores, consists of flow andesite, in part or in toto the " Premier " flow andesite of the 
principal mines further seaward. Outcropping at an elevation of 1,200 ft., however, some 
13 chains north-east of the shaft-collar, and again encountered in the extension of the main 
Moanataiari adit, is the complex of alternating flows and breccias extending southward from 
the upper Tararu Valley. The contact-plane between these two formations appears to dip 
about south-westward, and is thus in keeping with the structural conditions connected with the 
" Premier " flow rock throughout the whole Thames special area. 

In the Reuben Parr Section further seaward the underlying flow and breccia complex 
evidently hes below the deepest levels yet exploited. 

As in most of the claims in the upland side of the Moanataiari fault, belts of hard unaltered 
andesite are numerous, and occasionally of considerable dimensions. In the sections traversed 
by the Dixon's and Sons of Freedom reefs propylitic alteration is frequently confined to the 
more immediate belts enclosing the vein fissures. Thus one of the old Mines Reports§ states : 

* Approximate. f G.-3, 1889, p. 37. % " Handbook of New Zealand Mines," 1887, p. 290. 

§ Mines Report, 1887, p. 126. 



88 




or D r^ttOOM UvtL 



" There are three distinct channels of reef country, separated from each other by hard bands or 
bars of dioritic* rock. . . . The western channel encloses the Dixon's reef and several 
hanging-wall and foot-wall branches ; the central channel, the Sons of Freedom reef, speci- 
men leader and two foot-wall branches ; the eastern channel, the Success and Star of the 
South reefs." The statement quoted is, however, rather too sweeping, as in places propy- 
litised rock extends from one parallel vein-system to another. 

The Dixon's and Sons of Freedom reefs, together with several branching and subsidiary 
veins, have proved the important gold-producers of the north-eastern section of the claim. 

The general strike of these two leading veins is north- 
east - south-west, and the prevailing dip is to the north- 
westward at fairly high angles. Both these reefs when 
followed in strike and in dip have proved very lenticu- 
lar — in places pinching to a few inches, and again 
" blowing out" to 10 ft. or 12 ft., the average width 
being from, say, 3 ft. to 7 ft. These and the subsidiary 
veins were, however, found to weaken considerably on 
their hillward or north-eastern trend, and several 
transverse minor faults have been located in the 
vicinity of the old North Devon shaft. Topographical 
and other e\ndence suggests that a fault, probably a 
continuation of the Collarbone fault, with considerable 
downthrow to the westward traverses the countr}- in 
this locality, but it does not appear to have been 
actually encountered in the underground workings. 
The productive ground apparently lies on the hanging- 
wall side of this structural break. The pay-ore shoots 
on these two parallel reefs — the Dixon's and Sons of 
Freedom — were disposed " back to back," and proved 
practically continuous for 1,600 ft. on the line of the 
leefs. The occurrence of " specim(Mt " leaders between 
the major ore-bodies, as shown on the plan and 
section, was a feature of this richly productive ground. 
Other small auriferous veins branched from the hang- 
ing-wall of the Dixon's reef. A cross-course filled with 
clay and quartz grit, and striking transverse to the 
specimen leaders, intersected both the major veins 
within the productive area at a point about 6(K) ft. south-west of the main shaft. This is 
apparently a contemporaneous fissure, as no displacement of the inclined reefs is evident. 

The character of the ore was essentially the same as that encountered in the other 
richly gold-bearing areas of Thames— a highly pyritised quartzose veinstone. The presence of 
arsenical pyrites and ruby silver (pyrargyrite) is also recorded. 

The proved vertical range of the pay-ore is of considerable interest. Veinstone of 
bonanza richness may be said to have persisted from the outcrops of both veins (elevation, 
1,150 ft. above sea-level) to a vertical depth of about 400 ft. {i.e., about five stopes below 
the " 70 ft." level). In one locality, however, in the south-western portion of the workings 
near the boundary of the Whau Section, rich ore was found to extend down to a vertical 
depth of -190 ft., the horizon of the " 160 ft." level. Below the basal Umits of the shoots or 
runs in which bonanza ore was found the gold-content of the veinstone rapidly diminished, 
and the stoping of blocks from the Sons of Freedom level (580 ft. below the outcrops) proved 
unprofitable. 




TOlO AlSUKWA Ajtit. MOANATAIAIH TtjHNtL 



Vertical Section on line of 
Old Alburnia Company's Main Rise 

Scale of Feet 

1 00 UO )fw MO 

Hote Ssction Jtoqrammetic onjy fibovu ikiltcry ici'tl 



* The hard unaltered andeaite was in the early days of the field frequently described as diorite, 
6'— Thames. 



84 

The drift on what is apparently the Sons of Freedom reef in the Moanataiari main adit 
— over 1,050 ft. below the outcrop — and the limited amount of prospecting on the reef in the 
main rise connecting this adit with the Sons of Freedom level has revealed only barren or 
very low-grade veinstone. 

From the above description it will be noted that, notwithstanding the considerable 
elevation of the outcrops and the relatively great length of the ore-shoots in both reefs, the 
ascertained vertical length of the payable ore is not greater than that proved to obtain in many 
of the reefs which outcrop at lower elevations and even below sea-level. 

Apart from the veins of the Dixon's - Sons of Freedom Section none of the many reefs 
of the existing Old Alburnia Claim, which have in places pelded payable blocks of ore from 
shallow adit-level workings, call for special comment excepting those of the Messenger's Hill 
locality. Here the Point Russell or Reuben Parr workings have given a considerable 
amount of highly jjayable ores from several reefs — namely, the Reuben Parr, Dawn of Hope, 
Golden Age, and the Moanataiari Cross-lode. With the exception of the Cross-lode the.se 
veins have a general north-east - south-west strike, and the two first-named are in reality 
dropper veins which junction in dip with the hanging-wall of the big Golden Age reef. 

The Reuben Parr, the strongest of the subsidiary veins, here evidently junctions with 
the Golden Age above the level of the Moanataiari tunnel, but this junction has never been 
exploited. On its north-eastern trend the Reuben Parr can be traced for a long distance 
beyond the limits of the Old Alburnia Claim, following the ridge on the southern side of the 
Moanataiari Creek. Its width, as revealed in many adits, ranges from 5 ft. to 20 ft. 

In the particular locaUty under review the largest deposits of rich ore were obtained at 
and near the intersections of the Reuben Parr, the Golden Age, and various minor veins 
by the Moanataiari Cross-lode. This transverse vein, which averages about 1 ft. in width, 
and dips S.W. at angles approaching 45°, is one of the few persistent cross-reefs of the Thames 
field. In places it exhibits the character of a cross-course, being filled with pug and grit. In 
the vicinity of an intersected vein this pug-fiUing was usually found to be replaced by quartz 
which frequently afforded high-grade ore. It is interesting to note (see Plate facing p. 84) that 
neither the Golden Age nor any of the incUned parallel veins are displaced at their intersec- 
tion by this transverse fissure, a fact which impHes that no faulting has taken place along 
this Hue of fracture. 

Certain of the veins carried payable ore for about 200 ft. on each side of the Cross-lode ; 
and so numerous were small auriferous quartz veinlets and stringers in places between the 
stronger parallel reefs that the ground afforded what could almost be regarded as a stock- 
work. 

The elevation of the vein-outcrops in this Messenger's Hill locahty varied from 500 ft. to 
600 ft., and the downward Hmit of the payable gold was about the " 100 ft." level (elevation, 
215 ft.). Here, therefore, as in the Dixon's - Sons of Freedom Section, a maximum vertical 
range of about 400 ft. is indicated. This, however, it may be stated, marks in this section 
the locality of the deepest payable gold of any considerable importance on the upland side of 
the Moanataiari fault. 

The main Moanataiari adit passes under the old Point Russell workings, and is con- 
nected with the latter by a rise. In this adit the Golden Age reef has been located, but has 
proved practically barren. On the hanging-wall of the Golden Age, at an miascertained 
distance above this level, jimction in dip the Reuben Parr and other veins, which have 
proved productive in the upper workings. 

The work at present in progress in the Old Albiu'nia Claim is directed to the further 
prospecting of the veins in the workings at and above the Sons of Freedom level. The pass 
connecting this level ^^-ith the main Moanataiari adit should offer better faciUties for handhng 
low-grade ore than heretofore existed, 




Lower vertical limit - only approximate 



Long itudinal Section. Golden A g e Reef on line A-B 



Ore shoots of the Golden Age and Reuben Parr Reefs. 

— Showing the genetic connection of these shoots with the Moanataian Cross Lode.— 

— Scale of feet 



*ZSC 



100 50 

I ' ' ' ' ' 



100 



200 



bM< tui \o. 10.] 



[Face p. 8,>f. 



85 

Aloanataiari Extended Claim (Hidden Treasure) (area, 39 acres 2 roods 39 perches ; 
owners, the Point Russell Gold-mining Company, Auckland). — This claim, formerly known 
as the Alfred, is situated on the northern side of the Moanataiari Creek, and adjoins the Old 
Alburnia Claim. 

The recorded output from 1890 to 1908, as the result of operations by the Moanataiari 
North, Alfred, and Moanataiari Extended companies and the Hidden Treasure Syndicate, 
is 1,075 oz., valued at about £2,700. 

The country rock, as in the neighbouring Kuranui Claim, consists in part of the " Pre- 
mier " flow andesite and in part of the flow and breccia complex extending southward from 
Shellback Creek. The area hes on the foot-wall side of the Moanataiari fault, and, as usual, 
large belts of hard unaltered andesite are involved with the prevaiUng softer propylite. 

Several veins are known to exist on the property. The Alfred reef, which is generally 
considered to be identical with the Moanataiari Cross-lode of the Reuben Parr Section 
(Alburnia), has proved the most productive. Here, as in the area already described, this vein 
averages about 1 ft. in width, and in places carries pug and grit rather than a quartz filhng. 
Where the vein intersects propyhtised flow andesite it usually contains more compact vein- 
stone and better-grade ore than where it intersects the interstratified breccias. 

The lowest workings are from the old Alfred adit (elevation, 415 ft.), which has recently 
been reopened to admit of prospecting certain relatively large blocks which still remain intact 
on the Alfred reef. Payable ore has been obtained on this level, but the greater part of the ore 
mined in the past was derived from a block 200 ft. to 300 ft. long extending from the surface 
to within 110 ft. of this level. Copper-pjTites and zinc-blende were, in addition to iron-pyrites, 
found associated in small quantities with the quartz gangue. 

A large reef is seen traversing the spur on this northern side of Moanataiari Creek for 
a considerable distance. This is approximately on the hne of the Sons of Freedom vein of 
the Alburnia Claim, but its actual identity has not been estabhshed. An offset drive from 
the Moanataiari tunnel some distance westward of the Alfred workings has intersected a reef 
12 ft. wide, but apparently here, as in the deeper Reuben Parr workings, no payable ore was 
located. 

Reliance Claim (area, 15 acres ; owners, the Rehance Gold-mining Company, Auckland). — 
This claim covers a strip of coimtry lying within the upper watershed of the Moanataiari 
Creek, and is wedged between portions of the Old Alburnia and Thames claims. 

The old adit- workings known as the Orlando, Norwegian, and Bendigo Independent he 
within its boundaries. The recorded output is as follows : — 

Tons crushed. Yield. ^''^"^• 

Orlando Gold-mining Company (1889-97) . . 1,684 1,413 3,750 

Calhope (1889-96) . . . . . . 393 380 1,007 



2,077 1,793 £4,757 

The main reef of the area is the Reuben Parr, mentioned in the description of the Old 

Alburnia Claim. Several small subsidiary veins also occur-. 

The prospecting operations in progress are confined to projecting an offset crosscut from 

the Moanataiari main tunnel to intersect the Reuben Parr reef. 

Thames Claim (area, 94 acres 1 rood ; owners, the Thames Gold-mining Company, 
Auckland). — The Thames Claim covers a long strip of country, mostly confined to the ridge 
lying between the Moanataiari and Waiotahi creeks. Adjoining claims are the Old Alburnia, 
Rehance, Magnet, Trafalgar, West Coast, and May Queen. Prior to 1896 this ground 
constituted the Fame and Fortune and the Nonpareil* claims. 

* The original Nonpariel Claim was on the seaward side of the Moanataiari fault, and is now included in 
New Moanataiari Company's ground. 



86 

'riie returns recorded from the area subsequent to 1887 are as under : — • 

Tons cnished. Oz. ,. 

Pinafore Syndicate (1888) .. .. 73 198 525 

Fame and Fortune and Hauraki Golden 

Age Companies (1889-1905) .. .. 16,797 15,802 41,880 

Nonpareil Gold-mining Company (1896- 

1905) . . . . . . . . 1,697 2,389 6,60-1 

Thames Gold-mining Company (1906-8) .. 262 119 337 



18,829 18,508 £49,346 

Within the last two decades this ground has proved unprofitable to the various proprie- 
tary companies which have worked it. Certain tribute parties, however, having the advan- 
tage of the development- work done by these companies, have made fair profits out of some 
of the blocks. In the earlier days of the field the shallower workings in the Pinafore Section 
and on Foxes' and other reefs are stated to have afforded good returns. 

The ground has been worked from adit levels entering from the slopes of the Waiotahi 
and the Moanataiari creek-valleys and more recently by an offset crosscut from the main 
Moanataiari tunnel. 

The prevailing country rock is the " Premier " flow andesite, but in the more easterly 
or higher country a flow and breccia complex similar to that of the upper Karaka Valley- 
occurs. AVithin the propylitised rock-mass " hard bars " of unaltered andesite are not un- 
common. Probably the most extensive " bar " is that penetrated for some 600 ft. in the 
Thames crosscut from the Moanataiari tunnel. This is probably the offset counterpart 
of the extensive belt of hard rock separating the Waiotahi and Saxon workings in the vicinity 
of the Trenton shaft on the seaward side of the Moanataiari fault. Another " hard bar " is 
that separating the Reuben Parr and the Golden Age reefs at the existing adits. 

The Thames Claim lies altogether to the eastward or upland side of the Moanataiari fault. 

Two strong reefs — the Waiotahi-Cambria and the Golden Age — traverse this property. 
The former is the same as that worked in the Waiotahi and other mines on the seaward side 
of the gi-eat fault ; the latter is in all probability to be con-elated with the Caledonian No. 1 vein. 

In the western section of the Thames Claim these two strong quartz-bodies, as judged 
from the cross-section exposed in the Moanataiari tunnel-workings, are about 400 ft. apart, 
but on their north-easterly trend they gradually approach one another, and apparently 
junction in the vicinity of the Australasian crosscut. Each of these veins dips at angles of 
about 45° to the north-westward, and varies in thickness from, say, a foot or so to 30 ft. A 
feature of the Golden Age reef-system is the occurrence of huge, rather irregular masses of 
quartz in the propylitic rock on its foot-wall side. 

Numerous veins and stringers of quartz intersecting the country rock between the foot- 
wall of the Golden Age reef and the hanging-wall of the Waiotahi-Cambria contributed the 
bulk of the crushing-material raised by the eld Fame and Fortune Company. In the 
Balmoral level (elevation 502 ft.) and in the intermediate level some 50 ft. below this, was 
located the most productive ground of this locality. Certain sections of the Golden Age reef 
itself, mostly on the foot-wall portion, have also yielded pay-ore. A careful samphng of 
the vein where intersected in the Australasian crosscut was made by the writer. Its width 
here is about 28 ft. (38 ft. 6 in." on the horizontal), and the assay values of the four sections 
of uniform width taken in order from the foot-wall to the hanging-wall are £1 6s. 3d., 4s. Id., 
7d., and 5d. per ton respectively. 

In the western section of the claim the Waiotahi-Cambria reef is cut in the Thames 
crosscut from the Moanataiari tunnel. Carefully selected average samples taken from sec- 
tions across the full width of the vein, which is similar to that quoted above, gave on assay, 



87 

values varying from only 7d. to is. 6d. per ton. About 100 ft. from the hanging-wall of this 
large reef the Thames No. 1 reef was intersected in this main crosscut. Its average width is 
about 10 in., but beyond affording a few rather isolated bmiches of high-grade ore, it has been 
worked with unprofitable results. 

In this section, at the upper levels, are also the Liverpool Boys and the Wade reefs, 
worked by the Nonpareil Company. In the Thames crosscut these veins, which at the 
upper levels varied from 6 in. to 20 in. in width, appear to exist only as narrow stringers 
intersecting hard comparatively httle-alterod rock. 

Operations in this claim ai'e at present confined to the further prospecting of the 
Waiotahi-Cambria reef in the crosscut from the main Moanataiari tunnel. 

West Coast Claim (area, 4 acres 1 rood 25 perches ; owners, private individuals). — The West 
Coast Claim is a small block of ground lying between the New Moanataiari, Alburnia, and 
Thames companies' properties. For many years past it has been held by the present 
owners, and worked in a small way. From 1890 to 1908 some 439 tons of ore have been 
crushed, yielding 587 oz. of bulUon, representing a value of about £1,500. 

The main reefs which traverse the Thames Claim strike through this ground, at least in the 
upper levels, and from certain branch veins connected with them has been derived the 
limited amount of ore raised. 

Golden Drop Claim (area, 5 acres). — The Golden Drop is a sniail claim situated in the 
country drained by the headwaters of Waiotahi Creek, and forms part of the old London- 
derry and Candlelight claims. Subsequent to the earUer years of the field onlji a small 
amount of gold has been obtained, and this mostly from small " leaders." 

The Golden Age reef is observed to outcrop strongly some 20 chains south-west of the 
present workings, but is not visible further to the north-eastward. Crosscuts in several 
places in the Golden Drop Claim and adjoining ground have, it is said, conclusively proved 
that this strong vein, which, though more than once faulted, can be traced from the actual 
shores of the lirth to this outcrop, here terminates abruptly. Small veins exist for a few 
chains beyond the termination of the Golden Age reef to a point where dark, bioken, poorly 
consolidated rock, carrying absolutely no quartz, is encountered. This rock is evidently a part 
of the fragmental complex of the " Look-out Rock " area, and is barren of metalliferous veins. 

Magnet Claim (area, 75 acres 2 roods 20 perches). — The Magnet Claim lies within the valley 
of the Alabama, a branch of Karaka Creek, and extends across the ridge into the watershed 
of Waiotahi Creek. The elevation of the country varies from 700 ft. to 1,500 ft. 

The claim is now owned and worked by the Magnet Gold-mining Company, Auckland, 
but was formerly held by the Thames Talisman Company. In the earher days, and when 
practically the whole of the gold-output of the area was obtained (this is unrecorded), the 
ground was divided into smaller l)locks — the Jamaica, Candlelight, Multum in Parvo, Grand 
Trunk, and Bank of England. 

The country rock is a complex of more or less altered andesite flows and breccia-beds in 
which little definite arrangement can be detected. 

Numerous quartz veins were located and worked near the surface, and from certain of 
these workings the whole of the gold yielded from the area was obtained. Exploration at 
greater depths, especially in localities whore hard only slightly altered andesite has been 
encountered, shows that certain of these veins do not persist in depth. 

The reef at present being worked was cut by the Thames Talisman Company in the low- 
level adit (elevation, 816 ft.) at a point 850 ft. from the entrance. This level commands 
backs ranging from 300 ft. to over 500 ft. The reef occurs at the contact of breccia-beds with 
a heavy belt of flow andesite, the latter being altered for about 100 ft. from the reef, and 
there grading into hard rock. As might be expected, the fissure shows abundant evidences 
of faulting and crushing. The vein is markedly lenticular, " making " and feathering-out 



88 

repeatedly witUin short, intervals. Faults of later age than the vein tissiirc. but iormed 
prior to at least the concluding stages of mineraUsation, are recognisable. To one of these 
is apparently due the conspicuous bends in the vein south-west of the crosscut. 

The mineraUsation of the Magnet reef, which varies in width from a line to -i ft., is 
interesting. The vein-minerals, in addition to quartz, are pyrite, and probably marcasite. 
chakopyrite, enargite, and other cupriferous sulphides, zinc-blende, and barite. With thi* 
exception of pyTitc, the heavy minerals generally occur sparsely disseminated, or as isolated 
nests and patches. Free gold is occasionally seen. In places the vein-material consists of 
solid quartz in which the sulphides show Uttle definite arrangement. Again, the quartz 
contains curiy bands of dark finely granular sulphides. Highly mineraUsed dark-coloured 
pug and comminuted rock is not uncommon as fonning part of the vein-filling. General 
samples representing the various types of such material collected from points where no free 
gold was visible yielded on assay the following poor results : Gold, nil to 22 grains per ton ; 
silver, nil to 4 dwt. 3 gr. per ton. 

Apart from isolated patches of veinstone showing free gold, a very limited amount of 
high-grade ore is derived from a pug-seam which had been proved at the time of the wTiter's 
examination to follow the hanging-wall of the vein for 150 ft. or more in the drive. This 
seam, which " makes " and feathers out frequently, carries in places a high percentage of 
sulphides, and among them enargite as isolated grains or beautifully crystallized aggregates 
(see p. 4-0). Gold is frequently seen associated with the enargite of the pug-seam, and assays 
up to £300 to £400 per ton have been obtained. Again, this sulphide occurs with a very low 
gold-content. This is almost always so in the case of enargite associated with the solid vein- 
quartz. ^^ hy this mineral when occurring in pug should be so highly auriferous, and when 
occurring in the solid veinstone should be n on -auriferous, or almost so, is difficult to under- 
stand. Possibly in the case of the pug or clay the phenomenon of adsorption may be held to 
have contributed to the precipitation of the gold from migrating solutions. A great part of the 
sulphide-content of the vein at this level appears to be secondary, and, if so, so also is much of 
the gold. Pyrite occurs frequently recementing crushed and disjointed veinstone ; enargite, 
generally regarded as a secondary mineral, is probably in part derived from chalcopyrite. 
Barite, the sulphate of barium, is apparently the mineral of most recent deposition, and coats 
the quartz or sulphides in vugs and cavities. It is noticeable that in places where water 
percolating down through the vein is most abundant, the vein -filling contains more of these 
secondarv minerals, and is here said to be richer in gold than elsewhere. 

Operations in this claim are of purely a prospecting nature ; but, considering the amount 
of backs over the working-level, the discovery of a shoot of pay-ore at this horizon would 
present considerable possibihties. 

Arrindell Syndicate's Claims (area, 216 acres 2 roods 10 perches).— The Arrindell. a Glasgow 
syndicate, in 1904 acquired the Gloucester, Gloucester Extended, and George Turnbull claims, 
which are situated in the valley of the Lucky Hit, a branch of the Karaka Creek. The area 
was formerly worked by the Auckland Gold-mining Company. Lucky Hit Gold-mining Com- 
pany, Enterprise Syndicate, and the Gloucester Gold-mining Company (London). The gold- 
silver yield recorded from 1887 to 1908 is : — 

Auckland Gold-mining Company (1887) 
Lucky Hit Gold-mining Company (1888-9) . . 
Enterprise Syndicate (1892-3) 
Gloucester Gold-mining Company (1898-1902) 
Arrindell Syndicate (1905-8) 

Total .. .. ..481 1,078 £3,214 



Tons. 


Oz. 


Value. 
£ 


114 


305 


900 


206 


526 


1,578 


30 


17 


50 


65 


163 


492 


66 


67 


194 



8§ 

'fhe veins of the urea afforded at and near their outcrops small but rich patches of ore, 
from which profit was deri\ed by certain of the early prospectors and small syndicates. Al- 
though some of the companies subsequently working the ground mined a certain tonnage 
of highly payable ore, the pay-shoots proved so small that operations in every case resulted 
in a loss. All the work has been done from adit levels. The Gloucester Company (London) sank 
a substantial shaft a depth of 140 ft., with the intention of prospecting the ground at greater 
depth, but abandoned the venture without making any attempt at crosscutting. The present 
owners have spent a considerable amount of money, but have little to show for it excepting 
the importation and erection of a modern five-stamper battery. The workings were mostly 
inaccessible, and little examination was possible. 

More or less propyhtised andesitic flows and breccias, dipping in general to the north- 
eastward, constitute the country rock of the area. 

The veins, of which there are several, range in width from an inch or so to 2 ft. The 
principal ones are known as the Lucky Hit, Hansen's. Greenstone, Mary Helen, and Pride 
of Parnell. The strike is in general the prevaiUng one of the district^ — namely, north-east- 
south-west. 

The minerahsation is very similar to that of the veins of the Magnet Claim, distant about 
30 chains. The veinstone of the old dumps showed, in addition to quartz and pyrite, a minor 
amount of zinc-blende, chalcopyrite, enargite, and barite. Free gold was also seen in one frag- 
ment. Within the pay-shoots worked small patches of " specimen stone " were occasionally 
obtained. The assay of three samples of mineralised ore showing no free gold, taken from 
the dumps, returned a gold-content at the rate of only from 2 gr. to 5 gr. of gold and from 
1 dwt. to 2 dwt. of silver per ton. Evidently the enargite, which in these samples was 
associated with the sohd veinstone, is non-auriferous. 

In the unoxidized veinstone much of the pyrite is secondary, occurring as crusts lining 
vugs and cavities, and as tilms cementing fractured quartz. 

It is stated that small bunches of jasperoid (|uartz were of frequent occurrence in the 
upper workings on the Mary Helen vein, in the neighl)ourhood of pockets of rich ore. 

From the main low level — the Auckland adit — a winze was sunk about 30 ft. below where 
the shoot of ore was mined in Hansen's reef, but the prospects here, it is stated, were unsatis- 
factory. 

The value of the property is purely a speculative one, and an\- future expenditure should 
be in the direction of judicious prospecting. 

Halcyon Claim (area, 100 acres). — The Halcyon Claim is situated on the south-eastern 
side of Karaka Creek, the lowest adit entering from the creek-bank at an elevation of 490 ft. 

The claim is now being worked by the Halcyon Gold-mining Company, Auckland, and 
was formerly held at different times under the titles of the Halcyon, Ophir, and Manchester. 
The old Halcyon Company had the claim equipped with a battery, and obtained, it is said, 
very fair returns from the ores of the outcrops and upper portions of the veins. This battery 
no longer exists, nor is there any record of the amount of gold obtained. Since 1887 gold-silver 
bullion amounting to 72 oz. was obtained from 93 tons by the Ophir Gold-mining Company 
in 1893-4 ; while from the " Karaka Mine (old Halcyon) " a party of five or six men, from 
1891 to 1896, obtained 735 oz. (value, say, £2,200) from 1,822 tons. 

The Halcyon area marks the position of one of the local more highly propyhtised areas 
of the Karaka Creek valley. Andesitic flows and breccias form the country rock; and it is 
noticeable that the patches of high-grade ore were derived from those portions of the veins 
intersecting altered flow rocks, rather than breccias. 

The quartz veins have in general a strike of north-east - south-west or cast-west, and 
the vein fissures are probably all branches of a single local System of rock-fracturing. A 
disposition is noticeable for both vein fissures and fault fissures to follow where possible the 



90 

contact-planes between breccia- beds and massive andesite. The unoxidized veinstone shows, 
in addition to quartz and pyrite, chalcopyrite, and occasionally zinc-blende and stibnite. Enar- 
gite also appears to occur sparingly. A feature of the vein-material is the recementation of 
disjointed sparingly mineralised quartz by dark granular p}Tite. Pyrite is also noticeable 
as crusts deposited in vugs on the upper side of tooth-hke prisms of quartz, the lower side 
being quite free from this mineral. The deposition of secondary sulphides from descending 
solutions is therefore evident. 

The general run of this mineraUsed veinstone carries very low values in the precious 
metals. An assay of a sample taken from the vein followed in the low level yielded — gold, 
1 dwt. 1 gr. per ton ; silver, 4 dwt. per ton : value, 5s. 6d. The width of the vein where 
sample was obtained was 4 ft. 

The workings of the present company are mostly on portions of the vein-system west of 
the point where the gold of earlier days was obtained, and no payable ore has yet been located. 
A new prospecting crosscut is being driven further eastward than these workings, but no veins 
have yet been intersected. 

Southern Queen Claim (area, 84 acres 3 roods 20 perches ; owners, the Southern Queen 
Gold-mining Company, Auckland). — The Southern Queen Claim Ues mostly between the 
Collarbone Gully and Karaka Creek, and adjoins the May Queen, Trafalgar, Thames, 
Waiotahi No. 2, and May Queen Extended claims. It includes the old Atlantic ground, and 
was a few years ago held by an English Company, the Karaka Mines (Limited). 
The recorded gold-output since 1887 is as follows : — 

Tons crushed. Oz. ' , 

Karaka Mines (Limited), (1898-1900) . . 140 44-6 140 

Southern Queen Gold - mining Company 

(1906-8) . . . . . . . . 196 399-2 1,037 



366 443-8 £1,177 

The Atlantic reef, which strikes about north-east by north, has yielded practically all 
the gold won from this claim. The reef, which averages about 8 in. in width, has been drifted 
upon and stoped for about 3<KI ft., and the small pockets of jiicked stone occasionally obtained 
rendered certain limited blocks profitable. The better-grade ore was obtained at and east- 
ward of the intersection of a branch termed the " Blue " reef. 

The Hague-Smith (Onehunga) reef and numerous smaller veins traverse the property, 
but so far these have proved of little importance. 

Hard rock — unaltered andesite — is of common occurrence in the Southern Queen Claim. 
Even in connection with the Atlantic reef the range of propylitisation is very hmited, and 
hard rock is reported to exist in the viciiuty of each wall of the vein. 

The Mining Claims of Una Hill and Vicinitij. — The area considered here includes all 
that lying between the lower portion of Karaka Creek and the Hape Creek. The principal 
claims now in existence are known as the Lone Hand section cf May Queen, May Queen 
Extended, New Una, New Occidental, and New Dart. Smaller holdings are the Lord Nelson 
No. 2, Lord Nelson Extended, Fogarty's, Weymouth, and Ivy. Abandoned, or in part 
recently occupied, ground is that bordering the Hape Creek, and formerly known as the 
Anchor Mines of the Ethel Reefs Company. 

The rocks of this area are in the main well-consolidated fine-grained andesitic tuffs, 
with bands of flow andesite. Certain belts of massive andesite occur which may be intrusive. 
The bedded volcanics. judging from certain sections exposed in the underground workings at 
widely separate points, dip at low angles from a central point on the low grounds of Shortland. 
The greater part of the complex is highly propylitised, and the altered rocks have a charac- 



91 

teristic purplish-grey colour, which bocomos even more apparent when they are exposed to 
the atmosphere. Belts of hard dark comparatively unaltered andesite are not uncommon, 
and certain of these are of considerable dimensions. 

Practically the whole of this area hes on the eastward or upland side of the Moanataiari 
fault, which here skirts the western base of the steep-sided Una Hill. The elevation of the 
hill is about 926 ft., and the maximum elevation of the solid country on the seaward or down- 
throw side of the fault is about 140 ft. The downthrow of the fault here is certainly over 
600 ft., and possibly approaches 1,000 ft. 

The altered tuffs and breccias of the Una Hill upland area exhibit a strong resemblance 
to those penetrated in the Queen of Beauty shaft and in the A'anguard and Shortland Flat 
Avorkings, all on the downthrow side of the great fault. 

The Una Hill area, from the earliest days of the Thames Gokltield up to about the year 
1886 (two decades), was responsible for a substantial gold-output as the result of mining 
operations on numerous quartz veins at and near their outcrops. While the discovery of no 
bonanzas comparable in size with those of the Shotover - Prince Imperial line can be recorded, 
numerous patches of very rich ore were unearthed, which afforded considerable profits to small 
companies, syndicates, and private individuals. The productive veins varied in thickness 
from a fraction of an uich to 3 ft. or i ft. The smaller ones in particular were erratic and 
non-persistent, and were very frequently found to " cut out " at comparatively shallow 
depths. In places, however, the country rock was so seamed with these small rich stringers 
that it was quarried in bulk as a stockwork. Hero jx^rhaps to a greater extent than in any 
other locality on the Thames Goldtield has the localisation of rich ore been determined by 
the intersection of " flinties " with the quartz veijvs. So well recognised was this fact that 
these " flinties " or '" indicator veins " woro followed, on the chance of meeting with veins 
which they might intersect. As in other localities, minor faults were occasionally 
encountered, and the veins usually carried the best ore on the hanging-wall side of those 
intersecting fissures. 

Exploration at the deeper levels in the Una Hill area has, on the whole, proved dis- 
appointing. Patches of rich ore have been discovered fiom time to time, but the returns 
derived from those have proved ()uite inadequate to cover the cost of the long crosscuts and 
other development-work incurred. Since 1886 the gold-roturns have shown a steady decrease, 
and at present mining operations are here being conducted on a very limited scale. 

The stronger and more persistent veins of the area are known as the Adelaide, Moa, 
Duke's, Pride of Karaka or Loyalty, Occidental, German, Gibraltar, Hague-Smith or 
Onehunga, Noith Star, Jupiter, New Dart No. 1 and No. 2, and Rover. 

The character of the mineralisation in all these veins is much the same. The unoxidized 
quartzose veinstone carries invariably more or less pjTite, and occasionally — as sparsely 
distributed accessory minerals — zinc-blende, copper-pyrites, and stibnite. Fractured (juartz is 
frequently found recemented by dark granular secondary pyritc. Much of the veinstone is 
due to replacement of the wall-rock, especially the fractured and brecciated rock which has 
been includ<xl within the walls of the vein fissurt«. This replaced wall-rock is gcjierally inter- 
sected in every direction by stringers and veinlots of quartz. Cherty silica and. more rarely, 
ankerite are found cementing the comby quartz of vugs. 

The trend of almost all the veins, excepting the Hague-Smith, varies from north-east - 
south-west to east-west. The maps will show their relative positions and the direction of 
the dips. 

The Hague-Smith reef (also called the Onehunga) has rather a crescent-shaped course, 
in a general north-south direction, and may be regarded as probably the strongest and most 
persistent cross-reef on the Thames field. Its dip is invariably to the westward, at angles 
approaching 45°. This leef strikes up Te Papa Gully, apparently from a junction with the 
large Jupiter reef, and further northward may be traced through the North Star workings 



92 

across the ridge to and some distance beyond Karaka Creek. Tlu; Hague-Sniitli seldom 
carried payable gold, except at the intersections of certain smaller veins. 
The larger claims of the area may be briefly reviewed : — 

Lone Hand Section of May Queen Claim. — This claim has been worked from several 
adits entering from the hill-slopes on the eastern side of Karaka Creek. 

The gold - output prior to 1887 is estimated to represent a £ 

value of . . . . . . . . . . 9,500 

From 1887 to 1897 some 4, -486 tons of ore raised by the Lone 
Hand, Dives, and City of Manchester companies, jaelded 
6,152 oz. bullion, having an approximate value of . . . . 17,000 



Total .. .. .. .. .. £26,500 

The pay-ore was obtained mostly from small veins associated with the Adelaide-Moa Une of 

reef, and generally at the intersection of " flinties " with these veins. Good ore is said to have 
been followed down from the outcrops of the veins for a depth of nearly 250 ft.; but below 
this mining resulted in a loss to the proprietary companies. 

May Queen Extended Claim (area, 79 acres 2 roods 10 perches). — This claim, now the 
property of the May Queen Extended Gold-mining Company, Auckland, adjoins the New Una 
ground and the Lone Hand and St. Hippo sections of the May Queen Mine. Li- 
cluded within its boundaries is an area formerly known as the Adelaide. The statistics 
available refer only to the gold-returns of comparatively recent years. 

The Adelaide Gold-mining Company, from 1887 to 1900, mined £ 

2,241 tons of ore for 3,013 oz. bullion, valued approximately 
at .. .. .. .. .. .. .. 8,745 

The May Queen Extended Company, from 1896 to the end of 1908, 

raised 1,329 tons, for 970 oz. bullion, valued at . . . . 2,417 



Total .. .. .. .. .. £11,162 

The Adelaide has proved the most productive vein of this gTOund. The run of pay-ore 
had a longitudinal extension approaching 1,000 ft., and continued down in places over 300 ft. 
below the outcrop, the pay-ore gi'ving out usually some 40 ft. to 50 ft. below the floor of 
the No. 3 or Rocky Point level. This vein varies from a few inches to 4 ft. in width, and has 
a dip to the north-westward at high angles. A shaft was sunk 130 ft. below No. 3 adit, 
and a level driven from it to further prospect the Adelaide vein. The quartz-formation here 
measui'ed from 2 in. to 2 ft. in width, and afforded pockets of " picked stone " ; but, as 
mining-costs were high, owing in part to the necessary pumping and winding, the venture 
proved unsuccessful. If a further attempt is made to prospect this vein at greater depth it 
will probably mean the extension of certain of the May Queen levels, which are now within 
1,100 ft. of the Adelaide. Operations are at present confined to prospecting certain small veins 
in the adit-workings. 

New Una Claim (area, 57 acres 3 roods 8 perches). — This claim, which is a portion of the 
old Una ground, adjoins the Vanguard, May Queen Extended, and New Occidental claims 
and is worked by the New Una Gold-mining Company. Auckland. 

The total gold raised by this company (formed in 1903) amounts to 178 oz. (value, £497), 
derived from 290 tons of ore. The Pride of Karaka Company, which worked a part of this 
ground from 1891 to 1895 crushed 527 tons for 701 oz. of bullion. The area in earlier years 
contributed largely to the output of the Una Hill locahty. 

The Pride of Karaka, with its branch the German, and the Duke's, with its branch the 
Prince of Wales, are the principal veins of the claim, and proved consistent gold-producers 



98 

in the upper levels. The Pride of Karaka and the Duke's are both east-west veins, which 
dip towards each other at high angles. The former has been traced for over 1,000 ft. on its 
strike, and the latter even further, although it is, on its westerly trend in the May Queen 
Extended ground, faulted by the Adelaide vein. 

Development at the lowest adit levels has proved disappointing, and only a few men arc 
at present employed. 

New Occidental Claim (area, 19 acres 2 roods 15 perches). — This claim which is part of 
the old Una, adjoins the New Una, ^'anguard, and the New Dart ground, and is owned by the 
New Occidental Gold-mining Company, of Auckland. 

The recorded gold-silver output since 1887 is as under : — 

From North Star Section (acquired by Occidental Company ^ 

in 1896) (1887-96), 1,943 tons yielded 3,319 oz. ; approxi- 
mate value . . . . . . . . . . 8,800 

By Occidental and New Occidental Gold-mining companies 
(1889-1908), 1,757 tons yielded 4,579 oz. ; approximate 
value .. .. .. .. .. 12,200 



Total .. .. .. ,. £21,000 

The veins which have here proved productive are the Occidental, the Pride of Karaka or 
Loyalty on its eastern extension, and the North Star. The Hague-Smith has been prospected 
in certain places, but with unpayable results. From the official mining reports it appears that 
proposals have from time to time been made to follow the Pride of Karaka and Duke's veins 
until they intersect the Hague-Smith. This prospecting venture, which is coiisidered to hold 
out fair chances of success, has not yet been undertaken. 

Prospecting operations on a very small scale are now in ])rogrt«s in the New Occidental 
Claim. 

New Dart Claim (area, 82 acres 3 roods 20 perches). — This claim includes ground 
formerly held under the titles of Magnolia, Consols, Fortuna, tfec, and is the most southerly 
holding of the Una Hill group. 

The recorded gold-silver output sinci' 1888 is :— 

Magnolia Gold-mining company (1888-95) 
Consols Gold-mining Company (1889-95) 
Fortuna Gold-mining Company (1895-1903) 
New Dart Gold-mining Company (1906 08) 

Totals .. .. .. 4,636 2,775 £7,334 

For years prior to 1888 a considerable amount of gold was won. This was derived in great 
part from small veins at the intersection of " fiinties " in the shallow adit levels. The New 
Dart or Consols No. 2 vein, however, and certain others in the workings from the Consols 
shaft, also gave payable blocks of ore. Several large veins exist, and have been worked 
in places, but with Uttle or no profit. Two of these are the north-east - south-west trending 
veins. Jupiter and Gibraltar, the former being on the east side and the latter on the west 
side of the Hague-Smith cross-reef. 

The Fortuna Company, in 1895-96, quarried and milled 700 tons from a stock work- 
formation in the vicinity of the Gibraltar vein. No figures regarding the gold-yield from 
this test-parcel are recorded, but the result was stated to have been very disappointing. 

From the Consols shaft, sunk just above the jimction of Te Papa Creek with the main 
Hape Creek (elevation of collar, 192 ft.) four reefs have been exploited. These reefs, which 



Tons. 


Oz. 
yielded. 


.\l>l)roxJmate 

Value. 

£ 


1,209 


814 


2,160 


2,031 


1.329 


3,525 


1,228 


479 


1,230 


168 


153 


419 



94 

are known as No. 1, Alfred, No. 2, and Rover, all have a general north-east - south-west trend, 
and vary in width from 6 in. to 3 ft. Of these, the No. 2 proved the most productive. Its 
ore-shoot pitched south-westward at high angles, and was followed down to a stope or two 
below No. 4 level, where the vein was found to be abruptly terminated by a peculiar white 
granular fault rock. No exploration was undertaken below this horizon. On its south- 
western strike, also, this No. 2 vein is stated to have been terminated by a fault. This is pro- 
bably a subsidiary fault connected with the Moanataiari fault, which lies a little further to 
the southward. The results of mining on this vein at No. 4 level — 78 ft. below sea-level — 
are of interest as being the lowest horizon on the field at which payable ore has been located 
on the foot-wall side of the Moanataiari fault. 

Almost the whole of the New Dart Company's capital was expended in driving an adit 
level some 2,450 ft. in length, entering the hill-slopes at Parawai, and meeting the shaft at a 
depth of 165 ft. below the collar. This adit passed mostly through terrace-gravels and uncon- 
solidated volcanic ash and agglomerate of the Beeson's Island Series, which here flank the 
older vein-bearing rocks, and, as might be expected, was productive of no good results. 

It is a matter for regret that no attempt was made before the shaft machinery was dis- 
mantled to test the Dart veins below the No. 4 level. 

Anchor or Ethel Reefs Area. — This area, formerly held mainly by the Ethel Reefs 
Company, London, is now partly held in small blocks and partly abandoned. 
The gold-silver output of recent years is : — 



Souvenir Gold-mining Company (1890-96) 
Weymouth Syndicate (1893-1908) . . 
Anchor Syndicate (1897-99) 
Ethel Reefs Company (1899-1903) . . 
Daisy Syndicate (1906-8) . . 



Tons. 

217 

52 

858 

1,039 

4 cwt. 



Oz. 

yielded. 
" 107 


Value. 
£ 

278 


93 


235 


309 


815 


715 
167 


1,831 
405 



Totals .. .. .. 2,166 1,391 £3,564 

The parent reef of this ground is the Jupiter, which strikes north-eastward from the 
Hague-Smith cross-reef in Te Papa Gully. The Jupiter dips to the south-eastward at high 
angles, and varies in width from zero to 40 ft. From the Anchor adit crosscut it has been 
drifted on 1,000 ft., and some 600 ft. southward of this stretch it has been again cut in the 
Victory level. The foot-wall portion, of some 6 ft. to 8 ft. in width, usually affords the 
more solid veinstone — quartz with more or less pyrite and isolated bunches of zinc-blende and 
stibnite. Parallel stringers and partially silicified country rock usually forms the hanging- 
wall portion. The following samples were taken from the Jupiter for assay — (1) from out- 
crop in gully above Wallace's Smithy level ; (2) from ore-dump of Souvenir level ; (3) from 

foot-wall 8 ft. section in Victory level : — 

Value. 
£ s. d. 
(1.) Gold, 2 dwt. 12 gr. per ton ; silver, 3 dwt. 8 gr. per ton . . 12 4 

(2.) Gold, 5 dwt. 1 gr. „ silver, 5 dwt. 1 gr. „ ..108 

(3.) Gold, 15 gr. „ silver, 15 gr. „ ..027 

This large reef has afforded payable ore only from a few sections near its outcrop. In 

the deeper workings the veinstone has proved low grade. Certain hanging-wall branches 

— notably, Stephenson's and Prescott's — yielded small runs of payable ore, and occasionally 

pockets of " specimen ore." Intersections have, as usual, played an important part in the 

localisation of the high-grade ore in these veins. The small branch veins of the Weymouth 

holding have similar characteristics to the two branches mentioned. 



95 

Other Claims. — Many small claims now in existence, or which have been held from time 
to time in the Una - Hape Creek area, are Usted in the official reports as having produced 
in all during the past eighteen years bullion to the value of £5,400, as the result of 922 tons 
of ore treated. The larger producers were the Lord Nelson (£1,422), the Summer Hill (£715), 
and the Homeward Boimd (£550). The greater part of this output has been derived from 
small veins worked in shallow adits. 

Kuranui Claim (area, 73 acres 3 roods 5 perches ; owners, the Kuranui Gold-mining 
Company, Auckland). — The Kuranui Claim extends from Shellback Creek to a line some 
5 chains south of Shotover Creek. On the westward it is bounded by the foreshore of the 
harbour, and on the other sides by the Bonanza, Waitangi, Moanataiari Extended, New 
Moanataiari, and Kuranui-Caledonian claims. 

The present Kuranui comprises many small holdings of the earlier days, among which 
are Hunt's (Shotover), Kuranui, and Eurek;. In Hunt's, which was taken up on the 17th 
August, 1867, was discovered the first great bonanza of the field. This bonanza gave ore 
averaging over 21 oz. to the ton, and from it 29,466 oz. of gold were banked before the 31st 
December, 1868. Unfortunately, no figures other than those quoted on page 9 are avail- 
able, which have reference to the heavy gold-output of this claim prior to 1887. Since the 
year named the production has been very small. From 1887 to 1896, 58,946 tons, quarried 
from what was practically a stockwork-deposit, yielded 6,157 oz. of bullion, valued at, say, 
£15,400. From 1896 to 1908, 875 tons were mined, mostly from small veins, for 796 oz. of 
bullion, valued at £1,872 ; making a total of £17,272. 

Present mining operations are confined to adit levels, but in the past certain workings 
were projected from a shaft sunk to a depth of 358 ft. below the surface, or 260 ft. below sea- 
level. So numerous are the old surface-workings in the Shotover portion of the claim that 
the area resembles a rabbit-warren on a magnified scale. 

The company's mill comprises twenty head of stamps (700 lb. each, old type), amal- 
gamating and blanket tables, and ten berdans. The stamps and berdans are driven by two 
separate Pelton water-motors. 

Although the whole of the rocks \'isible within the boundaries of the Kuranui Claim 
are andesitic in character, the experienced miner has long since recognised a difference between 
the country rock of the northern and of the southern portion of the area. As the maps will 
show, the Tararu-Shellback flow and breccia complex gives place at the surface to the 
Premier " How andesite of Thames some 5 to 7 chains northward of Shotover Creek. 
Although the rocks are in the main highly propylitised, the two different formations are 
apparent. 

The position of the Moanataiari fault on its course througli the claim is mapped, and 
it is here sufficient to remark that all the payable gold has been derived from the reefs on the 
hanging-wall side of this fault. 

The veins of the Kuranui are numerous, but are hardly as persistent or well defined as 
those in the area further southward. Hunt's reef and Barry's reef, in Shotover Gully, have 
proved the most productive, but the ore-bearing zone or floor gave out in depth aljout 40 ft. 
above sea-level. 

The Hunt's or Shotover reef at the locality of the bonanza appears to have been a mass 
or " blow " of mineraUsed country rock interspersed with stringers and bunches of quartz. 
From the central mass highly auriferous (|uartz veinlets radiated in every direction. The 
foIlo\iing extract is taken from Hutton's report of 1868 : " Originally it (the lode) was dis- 
covered on the face of a waterfall, and was then about 5 ft. broad, with four or five small 
quartz veins running through it. It has now opened out to about 9 ft., but has no defined 
walls. The bed-rock is hard blue tufa, and the lode is the same, with nodules and veins of 
quartz, but it is not so quartzy as the Golden Crown lode. The quartz nodules are often very 
rich, and generally contain gold visible to the naked eye in small spangles and flakes. The 



96 

yield of gold gradually diminishes on either side of the lode, until, at about 18 ft. distant on 
the S.E. side, little or none is found. The same thing occurs on the N.W. side, but the 
distance at which it fails is not so well known, as it has not yet been sufficiently worked. 
This lode is worked open to the day, and is more a gold-quarry than a gold-mine." 

Hunt's reef, on its strike north-eastward from the locaUty of the principal bonanza 
deposit, was worked with highly payable results at various points ; so. too, was the parallel vein, 
Barry's, and also numerous branching or subsidiary veins ; but in all cases the pay-ore gave 
out at approximately the same horizon as did the Shot over bonanza. The vein- quartz of 
Hunt's, Barry's, and associated veins carries pyrite and it.s oxidation products. Zinc-blende 
and other sulphides are of somewhat rare occurrence. 

The quartz veins of the flow and breccia complex between Shotover and Shellback valleys 
exhibit mineraUsation similar to those in the claims further northward, where zinc-blende, 
copper-pyrite, and galena occur, in addition to pyrite. So far, these veins have afforded no 
payable results. The developments in the adjoining Waitangi Mine have led to the further 
prospecting of cei-tain of those reefs which appear to represent the ofTset line of the Waitangi 
or Dixon's(?) system. 

Kuranui -Caledonian Claim (area, 29 acres 3 roods 32 perches ; owners, the Kuranui- 
Caledonian Company, London). — This claim is next in hne south of the Kuranui, and is on other 
sides bounded by the Victoria, Waiotahi, and New Moanataiari properties. Within its limits 
are included many small holdings of earlier days, or portions of such holdings. First among 
these is the famous Caledonian and part of the old Golden Crown ; others are the Otago, Red 
Queen, Hazelbank, Inverness, Albion, All Nations, Junction, Long Drive, and Don Pedro. 

Of all the Thames claims, the Kuranui-Caledonian has yielded the heaviest gold- 
output, and the figures, if available, would have been of considerable interest. It is recorded 
that the Caledonian Company paid £554,440 in dividends in the first year of its existence 
(1869), the amount of gold obtained weighing about 9| tons ; the Golden Crown Company, 
irrespective of the large amount divided by the original holders, paid £141,904 ; the Long 
Drive Company paid £82,000 iu dividends : the Kuranui Company,* £41,277 ; the All Nations 
Company, £41,445. Since 1887, from which year official returns are available, the gold-yield 
has shown a gradual decline. The figures are as mider : — 

Tons crushed. 

Caledonian Gold-mining Company (1887-92) . . 7,768 
Kuranui No. 1 (1887-89) . . . . . . 642 

Kuranui No. 2 (1887-89) . . . . . . 53,726t 

Hazelbank Gold-mining Company (-1891-96) . . 11,141 
Kuranui - Caledonian Gold - mining Company 

(1896-1908) .. .. .. .. 7,739 



Yield. 


Value, 


Oz. 


£ 


3,925 




696 


60,904 


9,138 


(say) 


8,591 1 




4,381 


39,152 



Totals .. .. 81,016 36,731 £100,056 

The Kuranui-Caledonian shaft (collar- elevation, 91 ft. ; ), which has been sunk to a 

depth of 470 ft., gives access at four different levels to a maze of underground workings. 

These levels are opened from the shaft at the following depths from the surface : No. 1, 207 ft. ; 

No. 2, 262 ft. ; No. 3, 352 ft. ; and No. 4, 467 ft. This shaft is located in Moanataiari Valley, 

in the southern portion of the claim. In the northern section, where the pay-ore was confined 

to a shallower horizon, the veins have been worked mainly from the Moanataiari tunnel and 

smaller adits. 

The company's mill is rather an obsolete plant, comprising twenty head of stamps and a 

few berdans driven by water-power. 

* Part of this company's ground may have been within the limits of the present Kuramii Claim, 
t Stockwork-deposit. 



97 

The country rock of the Kuranui-Caledonian Mine consists in toto of the pyroxene andesitc 
of the ■' Premier " flow, in the main highly propylitised, but in places showing fairly large 
lenticular masses (" hard bars ") of comparatively little altered rock. This statement refers 
to the rocks visible at the surface and in the aheady exploited levels. The conditions inferred 
to exist at greater depths are considered in another section of this report. 

This property at the levels opened, it may be stated, lies altogether to the seaward of the 
Moanataiari fault. 

The veins which have proved the most productive are the Caledonian Nos. 1 and 2 in 
southern section of the ground and the All Nations in the northern section. Of the numerous 
others which have contributed to the gold-output, the following may be mentioned : the Red 
Queen, "WTieel of Fortune, Kelly's, Caledonian No. 3, Darby's, Young Americnn, Dukf's, and 
the Poverty. The large Waiotahi-Cambria reef crosses a corner of the property, but has on 
this stretch yielded no pay-ore. 

All the above veins pursue somewhat sinuous courses, but the prevailing strike, as the 
plans will show, is almost north-east - south-west, and the dip to the north-westward. 

The Caledonian No. 1 vein is the strongest and most persistent in the mine, and is notable 
as having afforded the great bonanza, which, as a concentration of exceedingly rich ore, has 
probably never been excelled in the annals of quartz-mining. With this vein is associated 
a loop or branch vein — the No. 2 — comparing in strength with the main body, and having 
in general a similar north-easterly trend. The Caledonian No. 1 varies in width from zero 
to 25 ft., and throughout the mine would probably average 5 ft. The aveiage inclination 
of these two veins, which form loops with each other in dip as well as in strike, varies usually 
from 45° to 50°. The famous bonanza occurred mainly in the No. 1 reef, at and seaward 
of its junction with the No. 2. It was first located in the Manukau Claim,* where the vein 
outcropped, and was from thence followed in dip into the Golden Crown Claim, and finally 
into the Caledonian (see sketch). Cox, who examined the area in 1880, thus describes this 




TOOKEY 



SHOOT OF GOLD 



Sketch-plan ok the Locality ok the Calkdoxias - Golden Crown lioxASZA (Cox). 



bonanza :| " This shot (of gold) followed a regular course through the Manukau ground and 
the Golden Crown until it met with a clay head, which, crossing it in a north-south direction 
with an easterly underlie, threw the gold in the reef along this course, and took it out of the 
Golden Crown into the Caledonian Claim, where it widened out into a large patch." 



* The Manukiiu Claim and part of the Golden Crown Claim are now included in the Waiotahi property. 
tRep. (l.S., vol XV, S. H. Cox. 

7— Thames. 



98 



" At the time tliis shot of gold was being worked (in the Go deu Crown) a small leader 
was noticed coming into the hanging-wall of the reef on the covirse of the shoot, but as it was 
poor close to the reef, no attention was paid to it. Subsequently this leader was opened up, 
and the vein was found to get more vertical shortly above the junction, and very rich gold 
indeed was obtained." 




Plau. 



Section through C-D. 



Section through A-B. 



Plan and Sections of the Junction of the Hanging-wall Leader with Xo. 1 Reef. Golden 

Crown Mine (Cos). 

Referring to the portion of the bonanza within the old Caledonian Claim, Cox remarks : 
" The famous specimen leader of the Caledonian Mine left the foot-wall of No. 1 reef, and 
after forming a half-moon, rejoined it again, being rich throughout, its course making no 
difference in its value. Between No. 1 reef and the specimen leader several other leaders 
occurred interlacing in every direction, and they all carried good gold." 

Summarising regarding this great bonanza, from the information that can be gathered 
it would appear that the locahsation of rich ore was genetically connected -with a junction 
of the two large veins — Caledonian No. 1 and No. 2 ; also with the smaller leaders or droppers 
and with a transverse clay-filled fissure which in the upper horizons crossed the No. 1 vein. 
The ore-shoot, except at the local deviation caused by the ■" clay head," was about vertical 
within the plane of the vein, which dipped north-westward at angles approximating 45°. 
Measured on the dip the shoot had a length of over 300 ft., and its greatest longitudinal dimen- 
sions could be placed at, say, 60 ft., although the transition to average-grade veinstone was 
a somewhat gradual one. The greatest stope-leiigth of the shoot was in the A^icinity of the 
No. 1 level of the Caledonian {i.e., 207 ft. below the shaft-collar). From this horizon down- 
ward the length gradually diminished, imtil at No. 2 level — 50 ft. below No. 1 — the bonanza 
gave place to much lower- grade veinstone. In the No. 1 level the parent vein ^^•ithin the 
bonanza-limits opened out to a maximum width of 22 ft., but here as elsewhere the richest 
band of " specimen stone " followed the foot-wall. This band in places was a couple of feet 
wide, and as much as 2 tons of " specimens " were brought down by firing a single shot. As 
is common in connection with such extraordinary ore-concentrations, gold was scattered 
throughout the wall-rocks, in this case particularly the foot-wall rock of the No. 1 vein. 
Numerous auriferous- quartz veinlets traversed the band or " horse " of comitry separating 
the No. 1 and No. 2 veins. Both the vein-quartz and the enclosing coimtry rock in the 
vicinity were highly p^iitised, the p}Tite usually exhibiting a splendent lustre. Zinc-blende 
and p)Targ}-rite (ruby silver), the latter mhieial lining vugs and cleavages, were also conspicuous 
in the rich veinstone. The occurrence of stibnite was also recorded. 

The All Nations vein, in the northern section of the property, pelded handsome returns 
to the several proprietary companies which in the early days worked various sections along 
its line of strike. With the All Nations is associated the Duke's reef and several other more or 
less parallel veins and branches. The general strike is north-east - south-west, and the dip 
is north-west at higher angles than the two Caledonian veins. In thickness they vary from 
I m. to 3 ft. or -i ft., -svith more conspicuous enlargements here and there. The pay-ore zone 
or floor had Httle extension below the Moanataiari tunnel-level, although the veins themselves 



99 

persisted downwards. Above tke tunnel-level rich ore was followed up in several shoots to 
the actual outcrops on Kuranui Hill, and in many cases the country rock in the vicinity of 
these outcrops was so seamed with auriferous-quartz stringers that it yielded profit on bring 
mined as a stockwork. 



N°l Level Caledonian 
1 Level Caledonian 




Plan & Section cf — 

— N°-^ I & 2 Reefs 

— Kuranui -Caledonian Mine 



toijkey Share 





■ J, .1.1 



Scale of Feet 

300 



The All Nations vein, which averaged 12 in. to 15 in. in width, carried pay-ore, although 
perhaps not continuously, over a horizontal di.stancc of 600 ft. or 7(M) ft. This and its associated 
veins showed minerahsation similar to the Caledonian veins. 

Numerous smaller and less persistent veins than those described existed in the area inter- 
mediate between the All Nation.s and Caledonian series. Certain of these yielded limited 
blocks of pay-ore, but on the whole they call for no special remark. 

The prospecting- work of recent years in the Kuranui-Caledonian Claim has been conducted 
at a loss, and the e.xisting levels are considered to be depleted of their pay-ores. The company 
is now subscribing to the main deep-level crosscut, which will afford access to the claim at the 
1,000 ft. level. (For remarks on deeper-level prospects, see pp. 121-12.3.) 

New Moanataiari Claim (area, 77 acres 22 roods 20 perches ; owners, the May Queen 
Gold-mining Company, Limited)*. The New Moanataiari Claim covers mostly foot-hill 
country lying to the seaward side of the Moanataiari fault scarp, but in places its boundary 
lies a few chains hillward of this salient topographic feature. In the northern portion a 
tongue-like strip protrudes from the main area towards the town flat and separatee the Saxon 
Claim from the Waiotahi Claim. Adjoining claims are all those Ipng between the Kuranui 
and May Queen ; also the Moanataiari Extended, the Alburnia, the West Coast and the 
Thames lying hillward. Holdings of earlier days lying wholly or partly within its boundaries 



* It is the 
7* — Thames. 



intention of the May Queen Compinj" to form a separate company to work this property. 



100 

are the Eureka Hill, Don Pedro, Morning Star, Heldt's, Golden Calf, Central Italy, Nonpareil, 
Cambria, Waitemata, and Moanataiari. 

The gold-output of the actual area now constituting the New Moanataiari Claim is not 
ascertain-v])le, owing in part to lack of early records, in part to the change of boundaries which 
have been effected from time to time ; for instance, the Point Russell, or Reuben Parr Sec- 
tion, formerly part of the Moanataiari and a fairly heavy contributor to the gold-yield, is 
now part of the Old Alburnia Claim. The following returns obtained by various companies 

may be tabulated : — 

Tons Yield. Value. 

Moanataiari Gold - mining Company, cmshed. Oz. £ 

Limited (1868-88) . . . . . . 141,569 389,193 

*New Moanataiari Gold-mining Company 

(formed 16/11/1888) (1888-96) .. 88,850 .38,238 103,243 

*Moanataiari Limited (Anglo-Continental) 

(1896-99) .. .. .. 10,935 6.168 16,356 

New Moanataiari Gold-mining Company 

(formed 5/10/1899) (1899-1908) . . 6,528 8,349 28,474 

Darwin Gold-mining Company, Limited 

(1881-87) .. .. .. .. 2.919 7,880 

Cambria Gold-mining Company, Limited 

(formed 4/1/1894) (1884-97) . . 30,915 55,456 149,731 

Trenton Gold-mining Company (1887-92) 1,142 1,364 3,683 



Totals .. .. .: 254,063 £698,560 

Where the tonnage has been given, the average value of the ore works out at about 
£2 5s. per ton, but during the profit-making periods the tenor was of course much higher. 

Dividends : The Moanataiari Gold-mining Company, founded in 1868, paid in dividends 
prior to the year 1887, the sum of £121,365, the capital paid up when the last dividend was 
declared being only £3,375. The Cambria Gold-mining Company, founded in 1884, and 
subsequently amalgamated with the Darwin Company, distributed among the shareholders 
prior to 1893 the sum of £80,475, the capit?J actually paid-up at this time being £1,676. The 
Nonpareil Company paid in dividends £14,670. 

Underground workings : The Moanataiari tunnel (size, 7 ft. 6 in. by 6 ft. 6 in. ; elevation 
of entrance, 26 ft.), the most substantial adit on the Thames field, gave access to the shallow 
workings of this claim. The sub-adit worldngs were carried out from shafts some of which 
communicated with the main tunnel-level. Of these shafts the Just in Time (collar-elevation. 
148ft.), in the Moanataiari Creek Valley, is the only one now in use. and is equipped v.ith a 
small winding-plant. The Cambria Section, while the Cambria Company was in existence, 
was worked from a shaft (collar-elevation, 203 ft.) in Waiotahi Creek. 

The country rock penetrated in all the workings of this claim is, excepting in the extreme 
western portion, the " Premier " andesite of the Thames special area. It is usually highly 
propyUtised, but " hard bars " are not uncommon. One of the most persistent of the " bars " 
or unaltered remnants is that through which the old Trenton shaft was sunk. 

The position of the Moanataiari fault at the surface and its computed position at the 
1,000 ft. level are indicated on the plans. 

The reefs which have proved productive are north-easterly continuations of certain of 
those worked in the adjoining Kuranui, Kuranui-Caledonian, and Waiotahi claims, together 
with numerous local branching and subsidiary veins connected with them. According to 
the Mines Reports, nine more or less distinct veins are recognised on the seaward or hanging- 



' Part of the ground held by these companies is now included in Albuvnia Claim. 



101 

Willi side of tlie great fault. Indeed, in viewing the plans of the New Moauataiavi the most 
striking feature is the maze of workings at the several levels on the seaward side of this fault, 
and the absolute Mank denoting the non-existence of mine-workings on the foot-wall side of 
the fault. 

In order of their occurrence from north to south the following veins may be briefly re- 
viewed : No. 3. or All Nations. Moanataiari No. 9, Caledonian Nos. 1 and 2, and the Waiotahi- 
Cambria. All of these present the same general type of mineralisation — quartz carrying a 
variable amount of iron-pyrites and occasionally small quantities of accessory minerals. " In 
the vicinity of rich stone the quartz often contains quantities of crystallized stibnite, while 
the stone itself is generally encrusted with dark ruby silver (pyrargjTite) .... Copper- 
pvTites is not found in the ore."* The occurrence of pockets or bands of specimen stone is 
as usual a feature of all the ore-shoots. 

The All Nations reef is about 15 in. in width, and carried good ore down to about 
8t) ft. below the level of the main tunnel. The bending-round of this vein fissure to the south- 
ward on approaching the Moanataiari fault is a feature worthy of note. The south-western 
e.xteiisioji of tliis formerly richly productive vein lies within the Kuraimi-Caledonian Claim. 

The Moanataiari No. 9 reef averages, say, 4 ft. in width, with local enlargements 
up to 10 ft. or 12 ft. It claimed considerable attention about the year 1877 (?), when it 
afforded what is known as the Moanataiari bonanza. This ore-shoot was struck in the 
soft, level from the old Moanataiari shaft {i.e., 80 ft. below the main tunnel-level) and at the 
locality where two small cross-veins — Heldt's and Wallace's — intersected the No. 9 reef. 
The latter here showed a width of 12 ft. or 14 ft., and dipped north-westward at fairly high 
angles. A fault dipping south-westward at low angles — apparently a hanging-wall branch 
of the main Moanataiari fault- terminated this strong vein at the actual north-eastern limit 
of the ore-shoot. The writer is indebted to Mr. John Kncebonc for the following rough sketch- 
plan and section constructed from memory : — 



OLD MOANATAIARI SHAFT 



^Intersection oT 
one of cross 

kuders (Heldti f) 




Sketch Plan and Section of the I.ocality ok the Bonanza oe the .Moanataiari No. 9 Reef. 

Within the ore-shoot the richest specimens were obtained from a compact band about 1 ft. 
wide in the large vein. From 8 cwt. to 10 cwt. of this e.vceptionally rich stone was sometimes 
broken out by a single shot, and it is recorded that " in a fortnight specimens were obtained 
weighing less than 2^ tons which yielded 14,600 oz. of gold."f Blocks of this rich stone were, 
it is stated, obtained in actual contact with the clay-filling of the fault fissure. The veinstone 
in the vicinity of the specimen band afforded a good tonnage of high-grade ore; and, as in 
the case of most of the other bonanzas of the field, the mullock or wall-rock, seamed with 
numerous interlacing veinlets, was payably auriferous in the pro.ximity of the ore-shoot. 

Mining on the No. 9 and subsidiary veins afforded patches of payable ore down to the 
150 ft. level — i.e., 120 ft. below sea-level and 50 ft. below the base of the bonanza shoot — 



* C.-3, 1896, p. 5]. 



t " Handbook of New Zealand Mines." p. 300, 1887. 



102 

but prospecting below this point at the 210 ft. level revealed nothing of a payable nature, 
this horizon apparently being below the limits of the productive zone. 

The Caledonian Nos. 1 and 2 reefs persist up to the hanging-wall of the main fault, and 
vary from 4 ft. to 6 ft. in width. Reports state that they have been worked out from the 
210 ft. level to the surface, but below this the blocks opened up proved too low-grade to extract. 

The \Vaiotahi-Cambria reef continuing north-eastward from the W'aiotahi Claim pursues 
a decidedly sinuous course throughout the Moanataiari ground up to the hanging-wall of the 
main fault, and with it is associated numerous branch, loop, and subsidiary veins. Witliin 
the Cambria Section of the claim under review a most pronounced feature is the complex 
forking of this big reef in the vicinity of the fault and the occurrence here of numerous " blows " 
or large irregular-shaped masses of vein-quartz. The natural inference is that the existence 
of this fault — generally regarded as a comparatively recent feature — has had a marked 
influence on some of the rock-fracturing which has preceded considerable mineralisation. 
This question is considered in another section of the report. 

In this reef was discovered in 1884 the Cambria bonanza, which for the following two 
years afltorded such handsome profits to the shareholders of the Cambria Company. This 
rich ore-shoot was located between the No. 2 and No. 3 levels, which opened at intervals of 
234 ft. and 294 ft. respectively below the collar of the Cambria shaft (collar-elevation, 203 ft.), 
and continued down about 20 ft. below the No. 3 level. It occurred at a point where the reef 
showed a marked local enlargement or " blow," and where it was intersected by both a cross- 
vein and a clay-filled fissure or " break." The following sketch of the reef at the locus of the 
bonanza is taken from the mine-plans : — 




Locality of the Cambria Bonanza 
N° 3 Level r Cambria workings. 



The portion of the reef carrying the rich ore varied from 4 ft. to 10 ft. in width ; the speci 
men stone usually occurred in a band in this reef measuring from 2 ft. to 3 ft. and also in the 
cross-reef, which would average about 1 ft. In stoping this rich veinstone " hauls of fioni 
2 cwt. to 5 cwt. of rich specimens were frequent, as much as 9 cwt. being got at one breaking- 
down. Some of these specimens were found to contain 2 oz. of gold to the pound of stone, 
and the average was about 1-J oz. to the pound."* 

The stope-length of the bonanza ore is stated to have measured from 25 ft. to 50 ft., and 
beyond these limits payable ore of average grade continued over a length of 200 ft. As a rule, 



* '• Handbook of New Zealaud Aliues," 1887, p. 308. 




Waiotaiii Mine, Waiotaiii Cmckk \'Ai.r,i;Y, TiiAMiotf. 



liulhtiii Su. 10.} 



[Fare p. 102 



103 

the pay-ore in the AVaiotahi-Caiubria reef was geiierally confined to the lianging-wall portion, 
and careful sorting was required to keep the average ore up to a payable standard. A regular 
network of small veins associated with the main reef here, as in the AVaiotahi Mine, contii- 
buted the greater part of the Cambria Mine's output subsequent to the year 1888. 

A considerable amount of prospecting-work was done at No. 4 level (344 ft.), but witli 
disappointing results, and here again it appears fairly certain that the basnl limit of the pro- 
ductive zone was reached. 

As showing the poverty of the big vein beyond the limits of the ore-shoot, it may be 
mentioned that a careful sampling of the transverse section exposed in the No. 3 level from 
the Just in Time shaft was made by the \vriter. The solid veinstone here showed an actual 
width of 16 ft. (24 ft. on horizontal), and three samples taken from the hanging-wall, median, 
and foot-wall sections gave values of Is., 9d., and 2s. 6d. per ton respectively. 

The company owning the New Moanataiari Claim will be contributors to the main 
1,000 ft. level crosscut scheme. 

Waiotahi Claim (area, 22 acres 3 roods 20 perches ; owners, the Waiotahi Gold-mining 
Company, Auckland). — This claim, situated near the mouth of the Waiotahi Creek Valley, 
is bounded on the north by the Kuranui Caledonian, on the east and south by the New 
Moanataiari, and on the west by the Victoria. It includes the old claims Waiotalii, Imperial 
City, Cure, Manukau, and part of the old Golden Crown. 

The Manukau and Golden CVown sections were the first to attain prominence, owing to 
the upper portions of the great Caledonian bonanza lying within their Umits. 

The following dividend-payments are recorded : Manukau Company paid £15,750 ; the 
Golden Crown Company, irrespective of the large amount divided by the original holders, paid 
£141,904 ; the Cure Company, which owned an adjoining claim (see sketch), paid £17,000. 

The Waiotahi Gold-mining Company has carried on operations continuously since 1873, 
and entered the dividend-lists in September, 1877. Since this date the property has proved 
the most consistent gold-producer on the Thames field. The regularity of the returns and of 
the dividend-payments which obtained for so many years may be attributed, however, to the 
mining policy pursued by the company rather than to any marked difference in the character 
of the ore-bodies from those of the Thames field generally From 1905 to 1907 the Waiotahi 
Company was mining extremely rich veinstone, and the ore-shoot located and worked at 
this time takes a leading place among those great shoots which have rendered Thames a classic 
bonanza field. The Waiotahi (Jold-mining Company's record is as follows : — 

Capital of Company — £ «. cl. 

1871 to 1905 (l:3th February) (l.oOO shares at 3 

1905 (13th February) to 1906 (18th August) . . 60.000 „ at 6 

1906 (18th August) to present time . . 240,000 „ at 1 6 

The actual capital paid up amounts to £15,C00. 

Yield. 



Results of Mining— Tons crushed. Oz. 

1871 to 1887 .. .. 22,211 29,905 

1887 „ Nov., 1904 . . . . . . 32,333 39.856 

Dec, 1904 , , 50 617 

_ I From bonanza and a few minor f*4,989 27,148 

I veins and low-grade material i +5.060 166 

,, 1906 I worked contemporaneously 18,002 82,640 

„ 1907 with bonanza I 11,562 55,912 

„ 1908 / ' 3,497 5,446 




97,704 241,690 £655,167 
*' Ore. t Mullock. 



104 

L)ivideiids paid — £ 

1871 to 1904 (November) . . . . . . . . 40,200 

1904 (November) to 1908 . . . . . . . . 354,600 



Total .. .. .. .. .. .. £394,800 

From the figures available reterriiig to the records of the Mamikau, (ioldeu Crown,* Cure, 
and Waiotahi oold-niijiing companies, it may l)e roughly estimated that the area at jjreseut 
coustitutiug the Waiotahi Claim has yielded gold-silver bullion valued at little short of a 
million sterling. 

Two shafts, equipped with the usual haulage machinery, give access to the underground 
workings. The main or Waiotahi shaft measures in cross-section 8 ft. by 4 ft. iii its upper 
part, and 12 ft. by 4 ft. in the lower or newer part. The Mary Ann shaft measures 10 ft. by 
3J ft., and, like the former, provides for two cage-ways and a ladder-way. The collar-eleva- 
tion of the main shaft is 62 ft. above sea-level, and levels are opened at the following intervals : 
No. 1, 119 ft. ; No. 2, 186 ft. ; No. 3, 256 ft. ; No. 4, 322 ft. ; No. 5, 381 ft. ; and No. 6, 
428 ft. 

The company owns two mills. The older, which is under the same roof as the winding- 
plant connected with the main shaft, comprises twenty stamps (600 lb. to 800 lb. each), 
amalgamating-tables, five berdans, and a Watson-Denny pan, and is driven by steam-power. 
The newer mill, purchased in 1905, consists of forty stamps of modern type and a cyanide 
plant. This mill is situated only a few chains from the other, but at a lower elevation, and 
is driven by water-power afiorded by the town supply. 

The comitry rock of the mine is altogether the "Premier" pyroxene flow andesite, in 
the main highly propylitised at the upper levels, but with a belt showing much less alteration 
in the southern portion of the property. This belt of hard dark rock underUes, with a pro- 
pylitic band intervening, the foot-wall of the Waiotahi-Cambria reef, and at No. 6 level is still 
foimd to be persisting downwards. Further reference will be made to this fairly heavy 
remnant of unaltered rock in another section of this report. 

The parent reef of the claim is the Waiotahi-Cambria, which pursues a very sinuous 
course in a general north-east - south-west direction through the whole central portion of the 
Thames special area. Its dip is to the north-west, at angles approximating 45°, and this 
underlie, at a depth of 600 ft. to 700 ft. below sea-level, carries it out of the Waiotahi 
Company's property — excepting in the western section — into the Kuranui-Caledonian 
ground. All the minor veins of the claim lying to the northward of the main reef — the No. 5, 
Imperial City, Cure, &c. — with their numerous subsidiary branches and stringers, may be 
regarded as droppers which terminate at greater or lesser depths on the hanging-wall of the 
flatter-lying main reef. 

Of the veins traversing the country on the southward or foot-wall side of the main reef 
only the Foot-wall Dropper and the Mariner's need be mentioned. The former is practically 
vertical, and strikes east-south-east from the main reef in the actual vicinity of where the 
great bonanza occurred. The Mariner's, striking and dipping in from the Victoria Claim, 
has been located at No. 6 level in the Waiotahi ground, where it veers round on approaching 
the Waiotahi-Cambria reef, and finally appears to die out in the belt of hard rock underlying 
this big reef. 

Prior to 1904 the various veins in the hanging- wall country of the main reef supphed the 
pay-ore. All the older official reports refer to the steady supply of crushing-material raised 
from mining a veritable network of small veins. Thus the following appears in the 1895 
Mines Report : " From twenty-five to thirty reefs and leaders are worked, varying from ^ in. 
to 3 ft. ; but the greater number are about 2 in. in width." Many of these were associated 

*Part of the old Golden Crown Claim lies within the boundaries of tlie present Kuranui-Caledonian Claim. 



Jo accompany Sulleiirv N^ fO , 



PLAN AND SECTION 

OF THE 

RICH BONANZA 

OF THE 

WAIOTAHI -CAMBRIA REEF 
WAIOTAHI MINE 

THAMES N.Z 

By Geo. Warne. Mine Manager 



Scale of Feet 



so u> 




"ill 1 1 I III,'- 

lil I I I I I II I-- 
1 1 I I I Ml II 
II A" III! ' 

1 1 Wi' SI I il.-- 

■ '?i'l',| 

'LiKiVl^'iV, i 

iivr iVi'- 
v,;::lii I II i.|Vi';. 

1' kiui ii|',ii| . 
"..\i 1 1 I 1 1 , 1 , 



— PLAN 

At NO 4 Level 



<7fV 



fly Atithoriti^ : John Maokay, Government Printer, 



TOO. 10/10. 447 



1U5 

with the No. 5 and the Imperial City reefs. All these small veins, as Cox remarks,* have 
been "subjected to numerous movements, caused chiefly by the .intersection of small clay 
heads or sUdes which are met with at places every 5 ft. or 6 ft. Along the slides, and close to 
them, gold is very frequently obtained." This writer has also recorded the fact that the 
black pyritic veinlets which intersect the wall-rocks were in places payably auriferous. The 
numerous minor faults had a prevailing dip westward ; and the pitch of the small ore-shoots 
associated with them in the reefs was necessarily in the same direction. 

Towards the close of 1904 a crosscut at No. 4 level intersected bonanza ore in the hanging- 
wall portion of the Waiotahi-Cambria reef — a strong body of veinstone, which, apart from 
subsidiary veins, had previously aftorded httle ore witliin the hmits of this claim. This reef 
presents a markedly sinuous course, and is evidently connected with a rather contorted 
fissure. Its width varies from a mere seam to 30 ft. or 40 ft. 

The great bonanza occurred in the vicinity of a marked bend or elbow in the strike of the 
vein, and at a point where the width of the veinstone showed considerable enlargement. 
The pitch of the ore-shoot was practically vertical within the plane of the vein, which in this 
section, it should be stated, dipped at higher angles than usual (50° to 60°). The plan and 
section of this bonanza and its enviroimient, compiled by Mr. George Warne, the company's 
manager, is of considerable interest. The richest ore, it will be observed, was confined to a 
lensoid pipe, measuring about 107 ft. in length and 32 ft. by 4^ ft. in cross-section. This very 
rich pipe was surrounded by highly payable ore, which graded into poorer though still remu- 
nerative ore, and finally into low-grade non-payable veinstone. The position of the foot 
wall dropper, the veinstone of which would be classed as " highh- payable," is also indicated. 
The whole vein is faulted a distance of about 6 ft. by an open water-bearing fissure, the off- 
set portions being as sharply demarcated as the section indicates. A persistent baiid of 
sUckensided clay or pug separated the veinstone from the wall-rock above, but not below, 
the intersection of this open fault-fracture. The thickness of tliis puggy band — about 4 ft. — 
seems remarkable in view of the small displacement which is indicated in the section. It is 
evident that the formation of both this pug selvage and the open watercourse, which is related 
to it, post-dated the deposition of the bonanza ore. The occurrence of small highly inclined 
veins of rich ore crossing the " liighly payable " veinstone at intervals above, but not below 
the faulting cross-course is also a curious feature. 

The reasons for such an e.xtraordinary locali ation of rich ore are certainly not obvious, 
and only a careful daily examination while sloping operations were in progress might possibly 
have led to definite conclusions being drawn. At the time the writer's survey was made only 
filled-in stopes marked the site of the great bonanza, and had it not been for the valuable 
data plotted by Mr. Warne, the record of the general conditions relating to this great ore- 
shoot would have been very incomplete. 

The total amount of gold-silver bulUon extracted from this shoot was valued at over 
£450,000. As showing roughly the distribution of the ore, it may be stated that the first 
stope above No. 5 level accounted for bullion valued at £-t<>.(MK). and of this amount about 
£30,0(J<) may be accredited to that portion which lay within the very rich pipe. 

As in the case of the Caledonian bonanza, the rich veinstone in the Waiotahi was very 
highly pyritised throughout, and irregular bands of almost solid pyrite were occasionally 
present. The other sulphides common to the field were apparently represented in relatively 
small quantity. The veinstone generally was very considerably fractured and disjointed, and 
the very rich ore was not, as is usually the case, confined to a well-defined compact band in 
the big vein. Heavy, rough, boulder-hke fragments consisting of " specimen stone " worth, 
say, from 1 oz. to 4 oz. of gold to the pound were irregularly distributed throughout rather 
cavernotis veinstone of lower tenor. 



' U.S. Kej). 1882, 1). 31. 



106 

It will 1)0 noticed that the vertical extent of the " veiy rich " and " highlv payable " ore 
ranged from 295 ft. to 380 ft. below the shaft-collar (elevation, 62 ft.) and that payable ore 
was carried down to No. 6 level. 428 ft. Below this level winzing and stopiug below the 
shoot throughout a vertical distance of 45 ft. revealed only barren or low-grade veinstone. 
The minor ore-shoots of the Cure and other veins also terminate at about No. 6 level, and it 
would appear that the basal limit of this particular productive zone has practically been reached 
in the Waiotahi Claim. 

Operations are at present confined to stoping out various blocks at Nos. 4, 5, and 6 levels 
on the main reef and subsidiary veins. The systematic way in which the mine was pro- 
spected and opened up while the bonanza ore was being extracted has made available these 
blocks of ore, which have continued for the past two years to yield payable returns. 

The company is a contributor to the proposed deep-level crosscut scheme. 

Victoria CInim (area, 73 acres ; owners, the Victoria Gold-mining Company, Auckland). — 
The Victoria Claim covers part of the flat ground upon which the Grahamstown Section of the 
Town of Thames is built, and also an adjacent foreshore block lying to the northward of the 
Goods Wharf. Adjoining claims are the Kuranui, Kuranui-Caledonian, Waiotahi, New Moana- 
taiari, Saxon, and the foreshore claim — Thames Deep-levels Consolidated. Holdings of 
earlier days included within the boundaries of the Victoria are the Imperial Crown, Tookey's, 
Golden Gate, Prince Imperial, and part of the Crown Prince and Hand-in-hand. 

The only available record of the gold-yield is as under : — 

Tons Yield. Value. 

Prince Imperial Gold-mining Com- trashed. Oz. £ 

pany (1881-86) . . . . 31.725 43,094 119,314 

New Prince Imperial (1887-90) . . 2,889 3,327 9,232 
Victoria Gold - mining Company 

(1891-1908) .. .. 6,684 7,400 20,274 



41,298 53,821 £148,820 

Dividend-payments amounting to £60,750 by the Prince Imperial Company prior to 1886 
are listed. The capital of this company was 18,000 shares at £1 each, and uj) to 1886 only Is. 
per share had been called up. 

Access to the present workings of the Victoria Claim is afforded by the small winding- 
shaft sunk and equipped by the Prince Imperial Company. From this shaft (collar-elevation, 
7 ft.) levels have been open at the following intervals : No. 1, 88 ft. ; No. 2, 144 ft. ; No. 3, 
244 ft. ; No. 4, 333 ft. ; No. 5, 421 ft. ; No. 6, 492 ft. ; and No. 7, 562 ft. 

The old Big Pump shaft,* sunk by the Imperial Crown Company, lies within the northern 
section of the Victoria property. The main crosscut, projected from this shaft through various 
claims at a depth of 640 ft., is now under water, and is more conveniently discussed in the 
section of this report dealing with the Thames deep levels generally. 

The country rock visible in all the accessible workings of the Victoria Claim, with the 
exception of that at one particular locality, appears to be referable to the " Premier " flow 
andesite. This is on the whole highly propylitised, but less-altered remnants (" hard bars ") 
are not wanting. Two of these remnants, which appear to be really lenses, cutting out 
both near the surface and in the lower levels, have been encountered. One lies within 
the altered country rock separating the No. 2 and the Mariner's reef ; the other lies to the 
foot-wall side of No. 2 reef, and in the two upper levels separates this reef from the branching 
Beach " lead." The one point in the workings now accessible where a distinct change from 
the prevaiUng rock-formation appears is in the long south-west crosscut at No. 4 level. 

* This pump-shaft and a reserve enclosing it is vested in a trust. 



107 

This crosscut iutersccts the Waiotiihi-Canilniii roef ut a poiut within l-iO ft. of tho most 
westerly angle of the Victoria-Waiotahi boundary, and from the foot-wall side of this vein 
to a point 150 ft. eastward andesite breccias have been intersected. This probably impUes 
the existence to the westward, especially in the down-faulted seaward block, of an extensive 
area consisting of interbedded flows and breccias. 

The veins which in the Victoria Claim have proved productive are the No. 1 (Mariner's), the 
Prince Imperial No. 2, the Beach lead, and thi^ N'ictoria. All of these have a general north- 
east - south-west strike and a dip to the north-west. The Mariner's is the strongest and 
most persistent of these veins ; and the others, as the maps and sections will show, are 
branches connectc^d with it either in strike or in dip. This vein-system is faulted by a trans- 
verse clay-tilled fissure which Ues about 100 ft. seaward of the Prmce Imperial shaft, and dij's 
south-westward at angles of 75° to 80°. This fault fissure has been followed at various levels for 
a long distance, and the several veins exhibit normal offsets varying from 8 ft., to 22 ft. 
according to their dips. If the fault-movement has been purely one of subsidence, a 
downthrow of 28 ft. is here indicated. A fault transverse to the veins also exists about 
2(K) ft. north-east of the shaft, and has effected normal offsets of the cjuartz-bodies, ranging 
up to 25 ft. 

The Prince Imperial No. 2 vein, rather than the stronger No. 1 or Mariner's, has proved 
the more productive ore-body of this claim, since it afforded what is known as the Prince 
Imperial bonanza. Tliis vein varied from a few inches to 3 ft. in width, and within the limits of 
the bonanza shoot the rich " specimen stone " was confined to a well-defiiu^d compact band 
from 2 in. to 9 in. wide. This band was, it is stated, usually confined to the foot-wall side. 
The bonanza ore was first struck at No. 4 level in the sinking of the shaft. Subsequent de- 
velopments resulted in the ore-shoot being followed up to near the floor of No. 3 level, and 
down to a stope below No. H level. The actual vertical limits of the ore-shoot may thus be 
regarded as having exteud<xl from 260 ft. to 500 ft. below the collar of the shaft. Tfiis rich 
shoot thus persisted to a horizon 175 ft. lower than the rich portion of the Waiotahi bonanza, 
some 10 chains further northward, and even 120 ft. deeper than the point where the payable 
ore in the Waiotahi gave out. 

The stope-length on this Prince Imperial bonanza at No. 5 level measured about 4:50 ft., 
and the pitch of the shoot was seaward — i.e.. south-westward — at high angles. The rich 
ore was found on both sides of the highly inclined fault previously refened to as traversing 
the country 110 ft. west-south-west of the shaft, and displacing laterally this No. 2 vein 
some 8 ft. 

Minerahsation within this ore-shoot is stated to have been similar to that of the Waiotahi 
bonanza. Pyrite was abundant both in the quartzose veinstone and in the adjacent country 
rock. Zinc-blende was here, as in many other places, usually counted a favourable " indicator " 
mineral, and other sulphides, such as chalcopNTite, were occasionally observed. Small p\Titic 
veinlets and " flinties " intersected the wall-rocks, and at their contacts with the vein 
augmented its gold-content. 

The Mariner's reef, in the workings from the Prince Imperial shaft, varied in width from 
a few inches to 7 ft., and has yielded some fairly large blocks of payable ore. On its south- 
west strike this vein, at No. 4 level, junctions with the No. 2, 140 ft. seaward of the Imperial 
fault, and it is significant to note that the stopes on the joint continuation of tbe.se two veins 
were carried right up to the " seaward slide " on pay-ore. The Mariner's reef, it may be 
remarked, appears to show increased strength with depth, since it is reported to have shown 
a width of 20 ft. of soUd quartz where intersected in the 640 ft. crosscut from the old Big Pump 
shaft. 

Between the Mariner's reef and the Waiotahi-Carabria reef several (juartz-bodies have 
been intersected in the long south-west crosscut at No. 4 level. The identity of these is un- 
known, and so far they have afforded no pay-ore. Beyond the Waiotahi-Cambria reef, which 



108 

bore «!xhil)its very lo\v-t;raclc qiuirtz, for a width of 20 ft. a vciy larj^e poorly defined quartzose 
formation was cut. This may probably be correlated with a large pvTitised ffinty vein-formation 
exposed in the No. 6 level of the Waiotahi Mine, some 130 ft. from the hanging-wall of the 
main reef, but in neither locality do assays show it to contain a gold-content of more than 
6 gr. or 7 gr. per ton. 

The present mining operations in the Victoria Claim are confined to a vein which lies 
between the Mariner's and the Victoria reefs, evidently a hanging-wall dropper of the former. 
The offset portion of this dropper beyond the eastern fault is also being worked, and, as the 
corresponding part of the Victoria reef has apparently not yet been located eastward of the 
fault, further exploration here appears advisable. 

The company is a contributor to the proposed joint deep-level crosscut scheme. 

Saxon Claim (area, 62 acres and 30 perches ; owners, the Saxon Gold-mining Company, 
Limited, Auckland). — The Saxon Claim is an irregularly shaped area comprising a portion of 
the Thames town flat, and also an adjoining section of the foot-hill country. It is bounded 
by the Victoria, New Moanataiari, and May Queen claims, and the foreshore claim — Thames 
Deep-levels Consolidated. Former holdings included within the Saxon boundaries are the 
Exchange, Old Beach, Golden Run, Cardigan, and part of the London and the Mariner. 

The gold-silver output prior to the year 1887 is not recorded. " The Handbook of New 
Zealand Mines " (1887), however, states that " The mine was very successfully worked in the 
early days of the field by the Crown Princess Company, which obtained some thousands of 
ounces of gold from the No. 1 and No. 2 levels." The following data will indicate ap- 
proximately the output of this claim since 1887 : — 

Saxon (1887-93) 

Cardigan (and Thamcs-Hauraki) (1895-99) 

May Queen (Saxon Section was held by this 

company ; returns fi'om May Queen and 

Saxon sections are bunched), (1894-96) 

Say, one-quarter of above is from Saxon 
May Queen - Hauraki — 

Saxon Section (1896-97) 

Cardigan Section (1897-98) .. 

Cardigan Section (1898-99) . . 
Returns from May Queen, Saxon, and 

Cardigaii sections bunched (1899-1903). 

Probably half of this should be accredited 

to area now within Saxon Claim 

Say one-half of above is Saxon 
New Saxon (1904-8) 

Totals .. .. .. 64,557 43,980 £125,485 

The recorded dividends paid by the Saxon Gold-mining Company (1887-93) total £15,417. 
on a paid-up capital of £7,083. 

The principal access to the mine-workings is afforded by a vertical shaft (size. 10 ft. by 
4|ft.), with a collar-elevation of 6 ft. Levels are opened at the following intervals : No. 1, 
106 ft. ;. No. 2, 177 ft. ; No. 3, 247 ft. ; No. 4, 317 ft. ; No. 5, 383 ft. ; and No. 6, 452 ft. 
Surface equipment consists of a winding-plant and the usual accessories. 



3ns crushed. 


Yield. 
Oz. 


Value. 
£ 


50,236 


28,032 


81,750 


240 


375 


1,003 


12,491 


12,423 


34,763 


3,123 


3,106 


8,691 


638 


579 


1,533 


1,296 


1,326 


3,577 


2,338 


2,218 


6,131 


11,668 


14,830 


40,289 


5,834 


7,415 


20,140 


852 


929 


2,660 



109 

In 1899 a small prospertiiifr-shaft was sunk to a depth of 94 ft. from a fhambor on the 
Saxon No. 1 reef at No. 6 level. From the bottom of this shaft, which is about 630 ft. north- 
eastward of the main shaft, certain reefs have been intersected and worked to a limited extent. 

The prevailing countrv rock exposed in the Saxon workings at present accessible is the 
" Premier " pvroxeno-andesite, all highly propylitised. The mine-plans, however, show that 
in the more easterly and north-easterly workings there is a considerable development of hard, 
dark, unaltered andesite. A narrower belt or " hard bar " of this same rock — probably a 
western offshoot of the main eastern mass—is stated to exist between the Saxon and the Queen 
of Beauty workings. An important section is exposed in the southern end of the Saxon No. 2 
level, in the vicinity of the Cardigan No. 2 reef. Here the flow andesite, which has continuous 
extension southward to this point from the Shotover Creek, gives place to stratified tuffs. 
dipping to the south-eastward at angles approximating 30°. These tuf?s are evidently part 
of the flow and breccia complex, penetrated in the Queen of Beauty shaft down to a 
depth of about 800 ft., which complex has still greater devcilopment in the area further 
southward. 

The principal veins located in the claim are the Saxon Nos. 1 and 2 and the Cardigan 
Nos. 1 and 2, all of which have a general north-east - south-west trend. With certain of these 
veins are associated smaller branches, as the map will show. The dip of the No. 2 reef and its 
hanging-wall branches is towards the north-westward— /.p., in conformity with the general dip 
of all the veins northward from here to the Shotover. The Saxon No. 1 vein and also the 
Cardigan veins, southward of the Saxon No. 2, dip towards the opposite point of the com- 
pass at high angles, and conform with the Queen of Beauty veins still further to the south- 
ward. 

To the south-westward all the veins are terminated on their strike by the Beach " slide," 
which here dips westward or seaward at an angle of about 55°. Nearing this " slide " the 
Saxon No. 2 vein forks into three or more branches, and on the other hand the two otherwise 
parallel Cardigan veins converge and meet the " slide " as -a single vein. To the north-east- 
ward all the veins give out or become pinched to more scams in the hard unaltered andesite 
into which the propylite grades. The length of the workings oii, say. No. 4 level, between 
these limiting points, is, in the Old Saxon Section, 1,200 ft., and in the more southerly Car- 
digan Section, about 800 ft. Within these limits the veins have in places been subjected to 
faulting. One of these lines of fault crosses at No. 5 level, about 7(K) ft. eastward of the main 
shaft, and dips to the north-east. This line of fracture is possibly to be correlated with the 
main eastern fault of the adjoining Victoria Claim. The fault traversing the country about 
100 ft. west of the Prince Imperial shaft should also cross the Saxon reef system, but its 
effect is not apparent from an inspection of the mine-plans, and possibly its downthrow 
gradually diminishes and dies out in this direction. 

The Saxon Mine, as the statistics submitted will show, has yielded a good deal of gold. 
This has been won from ore averaging in value about £2 per ton on the aggregate, and about 
£3 per ton when the name of the company appeared in the dividend lists. Although pockets 
and small shoots of " specimen stone " occurred in most of the reefs, and materially as.sisted 
in keeping up the general tenor of the ore milled, it cannot be affirmed that an ore-deposit 
of sufficient size, concentration, and value to be designated a bonanza has ever been located 
in this claim. 

In general it may be stated that the reefs of this claim varied from 6 in. to 5 ft. in width, 
and all of them afforded more or less pay-ore down to the floor of No. 6 level. The Saxon 
No. 2 reef was probably the strongest and most productive ; the Mines Reports of 1891 state 
in connection with this vein that the main run of gold at No. 5 level " was about 400 ft. long, 
and the lode varied from 3 ft. to 12 ft. wide." It is sufficient to note that the ore afforded 
by all the veins in the vicinity of the terminating Beach " slide " was as good, if not better 
than that in any other section along their courses. At the lowest level (No. 4) examined by 



no 

the writer the country I'ock and <jeneriil iniiu'ralisatioii in this direction are certainlv of 
favourable character. 

Regarding the prospects below No. 6 level, the lowest commanded from the main shaft, 
the mine-manager,* in liis annual report of 28th January, 1892, stated, " The prospect all 
along the floor of the No. 6 level is very encouraging ; indeed, more so than at any of the 
upper levels, especially east of the No. 2 break on all three reefs. Some splended specimens 
came from the drives on No. 1 and New reef, and these two reefs should junction about 75 ft. 
under No. 6 level. Both being strong lodes, and running in a splendid channel of country, 
there is every reason to believe that the future prospects on the lower level will be even better 
than from the upper levels." The only work done below the No. 6 level was by the May 
Queen - Hauraki Company in 1899, from a small subsidiary shaft mentioned previously. 
The writer is informed by the gentlemanf who was in charge of this work that httle was done 
on the veins at the No. 7 level. This prehminary work proved unprofitable, but, as it was 
sufficient to estabhsh the fact that coimtry rock of favourable character persisted downward, 
better results should be forthcoming from future operations. 

A consideration of the depths at which pay-ores have been obtained in the Victoria Claim 
to the north of the Saxon, and in the May Queen Claim to the southward, in addition to the 
prospects reported to exist at No. 6 level in the Saxon itself, leads to the conclusion that the 
base of the productive zone in this claim has not yet been reached. 

The company is a contributor to the deep-level crosscut scheme. 

May Queen Claim (area, 211 acres 2 roods 4 perches ; owners, the May Queen Gold- 
mining Company, Auckland). — The May Queen Claim covers a considerable area of the low- 
lying Thames Town Belt and a section of the foot-hill country extending eastward to and a 
little beyond Karaka Creek. 

Adjoining claims are the Saxon, Moanataiari, May Queen Extended, Vanguard, and 
Shortland Flat. Two of these — the Moanataiari and the Vanguard — are at present the pro- 
perty of the May Queen Gold-mining Company, but, as proposals are now on foot to form 
separate companies to work these particular claims, each of them is considered separately in 
this report. Holdings of the earher days lying within the boimdaries of the May Queen pro- 
perty are : the Queen of Beauty, Bright Smile (Piako), Bird in Hand, City of London, City 
of York, Queen of the May, Lucknow, St. Hippo, Lone Hand, and part of the Queen of 
Thames, Young Queen, and Old Cardigan. 

The old Lone Hand Section hes immediately to the eastward of Karaka Creek, and has 
been described in connection with the claims of Una Hill. It should here be stated that a 
Crown reserve measuring 1 acre 2 roods 5 perches, within which the Thames-Hauraki shaft and 
pumping-station is located, Ues in the central part of the Queen of Beauty Section of the 
claim. 

The available output figures relating to the May Queen claim are as follows : — 

Queen of Beauty Extended prior to 1887 
sold to the Bank of New Zealand alone 
(purchases by other banks and Sydney 
Mint are not recorded) 

Queen of Beauty Company (1893-94) 

Lone Hand Section (see p. 92), approxi- 
mate (to 1897) . . 

Crawford's Special (1889-93) . . 

St. Hippo (late Crawford Special) (1893-95) 

* The late Mr. T. A. Dunlop {vide C.-3, 1892, p. 42). 

t ill". W. H. Baker, now manager of the May Queen Mine. 



Tons 

c-nished. 


Yield. 
Oz. 


Value. 
£ 




135,877 


367,973 


73 


43 


120 
26,500 


525 


710 


1,955 


560 


761 


2,093 




rM\Mi:>-ll.\U! \K1 SllAl-T AM. 1'lM I'INi ;-ST.\T10.\. T|1AM1:;.<. 



/iu/lctiu Xo. 10.] 



[Face i>. liu. 



17,024 


17,383 

18,635 


48,657 


15,545 


50,677 


5,439 
6,669 


7,097 
6,559 


19,296 
18,648 



111 

Tons Yield. Value. 

May Queen (1890-96) (partly from area crushed. Oz. £ 

now included in Saxon Claim .. 20,147 20,489 57,348 

From May Queen Claim (say) 
May Queen-Hauraki (1896-1903) (mostly 
from Saxon ground) 

From May Queen Claim (say) 
New May Queen (1905-8) 

Total (approximately) . . . . 168.430 £485,242 

Where the tonnage has been given, the value of the on; has avoragod witliiii a fraction of 
£3 per ton. 

Dividends : Concerning the Queen of Beauty Extended Mine, " The Handbook of New 
Zealand Minos " (1887). states, " From the surface down to a depth of 350 ft. the reefs were 
worked by the various companies, and handsome dividends were paid for years." In connec- 
tion with the May Queen Gold-mining Company, the Mines Report for 1897 refers to two 
dividends having been paid in 1896 7 amounting to £2,304.* 

Accass to the priucipal underground workings of the May Queen Gold-mining Company 
are afforded l)V the Thames-Hauraki and the Queen of the May shafts, which are located 
within 440 ft. of each other. From the former — a State-owned shaft, having a collar-eleva- 
tion of 29 ft. — this company is working from levels opening at 747 ft. and 1.0<K)ft. respec- 
tively. From the Queen of the May shaft (collar-elevation, 93 ft.) levels hax'e been con- 
structed at the following intervals : No. 2, 264 ft. ; No. 3, 336 ft. ; No. 4. 411 ft. : No. 6. 
543 ft. ; and No. 7, 6(M) ft. (For May Queen levels, see Appendix, p. 126.) 

The geological structure of the May Queen- Queen of Beauty area is by no means easy 
to decipher from the limited sections exposed in the accessible workings. The south-easterly 
dipping contact of the andesitic ash or breccia beds with the underlying massive propylite 
(the "Premier" flow) evidently passes through the Thames-Hauraki shaft some distance 
below the 747 ft. level. This same contact-plane carrying carbonaceous materia! has recentlv 
been intersected at the l,0(X)ft. level in the May Queen's cros.scut at a point 17<) ft. soutli- 
eastward of this shaft (see section). 

Above this south-easterly dipping contact->plane irregularly bedded flows and breccias 
constitute thci whole rock-mass in the Queen of Beauty Section, and the same formation 
obtains throughout the workings in the May Queen Section. Some of these ash or brciccia 
beds exposed in the latter locality and in the drifts coimecting the two main shafts exhil)it 
stratification at angles closely approaching 90° — that is, the beds in places practically stand 
on edge. The reason for such a complicated structure is not obvious, but there is some 
evidence in favour of the view that this locaUty is adjacent to the crater of an ancient volcano. 
Normally inclined breccia-beds may therefore have been further tilted by local intrusive 
dyke-like masses of andesite which radiated from tliis centre of volcanic activity. Apart from 
the facts submitted, an examination of many of the " hard bars " exposed in the May Queen 
workings gives one the impression that they are intrusive rocks rather than interbcdded flows. 

The various rocks are in the main highly propylitised, but " hard bars " or less-altered 
remnants are not uncommon. Spheroidal masses of hard black andesite, popularly known 
as " boulders," are a feature of certain parts of the May Queen workings, and are encoun- 
tered even in the actual vicinity of the vein fbsures. 



*Probably liquidation payments on sale of property to an English company. 



112 

An examination of the May Queen workin{;s further confirms the fact alreadv noticed 
in this report (in connection with the Thames veins generally) that fissures in piopvlitised 
massive andesite (flow or intrusive) have constituted a much more favourable repository for 
pay-oies than have those in propylitised breccias or ash beds ; in other words, a vein where 
it intersects moderately hard altered rock of uniform texture is usually more productive than 
where it intersects the less compact softer " mottled " countrv. 

The principal veins of this property are the Queen of Beautv Xo. 1 (or Main reef), the 
Queen of the May, the Bird in Hand, and the Vanguard, all in the Queen of Beauty Section ; 
the May Queen No. 4 and the North-west, in the May Queen Section. 

The strike and dip of the several veins, as the plans will show, exhibit rather a lack of 
uniformity, and is in keeping with the rather complicated structure of the rocks which they 
intersect. The No. 1, or Main- reef, of the Queen of Beauty Section in its north-easterly 
strike jimctions \nth the No. 4 reef of the May Queen Section. The last-named vein, which 
exhibits an east-west strike, is probably to be correlated with the Cardigan No. 2 reef of the 
adjoining Saxon Claim ; but, as a good deal of imexplored groimd separates the workings of 
the two claims, actual identity cannot be established. 

The No. 1, or Main reef (strike north-east - south-west), is faulted by the Queen of the 
May reef (strike east-west), the offset of the former being about 35 ft. The east-west line 
of rock-fracturing is therefore in this particular case, if not throughout the vein-svstem 
generally, the more recent. 

The No. 1, or Main reef (Queen of Beauty), has proved the most productive one in this 
company's ground. In the upper levels it is divided into two branches, which dip towards 
each other, and unite also on theii- south-westerly or seaward trend. In dip these two 
branches junction about No. 5 level, say, 370 ft. from the surface, and the vein persisting from 
here downward to and below the 747 ft. level preserves an incUnation to the south-eastward 
at fairly high angles. 

The following extract regarding the results obtained in the upper workings is taken 
from '■ The Handbook of New Zealand Mines " (1887) : '' From the surface to a depth of 
350 ft. the reefs were worked by various companies, and handsome dividends were paid for 
years ; but at this point (about 350 ft. from the surface) the reefs became poorer, in conse- 
quence of being in a different strata of rock not so favourable for gold. However, on sinking 
the shaft to a depth of 537 ft. the reefs at No. 8 level were cut, and found as rich as they Lad 
had been above. A run of gold on one of the reefs was worked for a depth of three levels, or 
to 677 ft. from the siu'face, when it became poorer. " The foregoing quotation probably 
refers to the Main reef and its branches. Normally, this vein in all the workings was not 
very wide ; but considerable local enlargements must have been encountered, as it is stated on 
good authority that ninety-six stamps were at one time running on ore raised from the Bright 
Smile or Piako workings. The vein-stuff then mined was described as loosely consolidated 
dark-coloured material, which extended over a considerable stoping-width. The historical 
facts are vague ; but this deposit appears to have been a minerahsed sheer zone in ash or 
breccia beds, and was probably connected with the seaward jimction of the two upper branches 
of the vein. At one level the Main reef was worked out to the Beach " slide," but there is 
unfortunately no record of this on the mine-plans. At the present working-level — 747 ft. from 
the surface — this vein shows a width varying from 1 ft. to 3 ft., and where intersecting the 
propylitised massive andesite it is \-ielding payable ore. The veinstone is here highly pyri- 
tised, and generally of a darkish colour, but specks and blotches of gold are occasionally seen 
in the better-grade ore. On its course through the altered breccia country the vein is unpay- 
able, and is subject to numerous minor faults or breaks. 

The Queen of the May reef, which passes transversely through and faults the Main reef, 
has yielded several blocks of payable ore. 



113 

The Bird in Hand reef, which occurs to the southward of the Main reef, and is incUned 
towards it at high angles, has been worked over stretches of 400 ft. to 500 ft. along the hue 
of strike from the old Bird in Hand and Piako shafts. Payable blocks were stoped down 
to a depth of 250 ft. fi'om the surface. The Vanguard crosscut from the No. 8 level (550 ft.) 
Thames-Hauraki shaft intersected tliis vein ; but apparently it was here poorly defined, and 
carried httle or no pay-ore. 

The Vanguard is said to be a fairly strong east-west reef of irregular dip, ranging from 
2 ft. to 15 ft. in width ; but, unfortunately, little information regarding it appears to be avail- 
able. It has been exploited to some extent from the Vanguard crosscut (550 ft. level) men- 
tioned above ; also from a drive from the old Piako shaft at 423 ft. below sea-level ; and 
again at a shallower depth from the old Vanguard shaft. The vein intersects the iutwbedded 
flow and breccia complex which extends southward from the Thames-Hauraki shaft, and the 
plans show that cross-courses and minor faults are not uncommon. It is probable that the 
most westerly end of the drifts on this vein are not far from the Beach " shde." Park writes* 
concerning the reef : " The 700 loads of quartz which were crushed from it yielded at the rate 
of about 5 dwt. by the old battery process. The tailings were treated in pans by Messrs. Brown, 
of Tararu, and yielded an additional 6 dwt. or 8 dwt. per load. The shmes were then stacked 
and allowed to oxidize, and were subsequently treated at a further profit. The quartz was 
generally hard and compact, and was alwavs highly charged'with metallic sulphides, prin- 
cipally pyrites." 

In the May Queen Section of the claim the No. 4 reef, with certain of its branches, is the 
one which has contributed the major part of the gold output. From the Queen of the May 
shaft this vein, wliich varies from 1 ft. to 4 ft. in width, has been worked down to No. 6 level 
(721 ft. from the collar), and has afforded stoping-blocks exceeding 40<) ft. in length. At 
No. 6 level this vein, on its western strike, di^^de3 into two branches, one of which extends 
upwards only some 50 ft. and then feathers out in hard dark andesite. The vein has associated 
with it at and above No. 6 level two foot-wall droppers or loops. These are well-defined ribs of 
quartz, seldom more than 4 in. in width, but, affording as they do ore worth on the average 
from £12 to £16 per ton, they prove liighly payable. These loop veins show central druses 
often lined with " sihca," secondary pyrite, and sometimes baritc. The specimen ore is gene- 
rally associated with the intersection of " flinties " with the veins, and occasionally a regular 
network of these, varying from mere seams to bands 3 in. wide, traverse the wall-rocks. 

The " North-west " reef, although the largest in this section of the mine — its width varies 
from 3 ft. to 10 ft. — has not proved especially productive. It is evidently confined to a sheer 
zone, and the vein-quartz is frequently much mixed with brecciated and mmeralised coimtry 
rock and clayey selvages. Dark granular pyrite is abundant in the quartz and country rock 
within the walls of the fissure, and in places'causes the material to assume a dark colour. 
This reef and the No. 4 unite in the eastern portion of the workings, and at No. 4 level this 
junction afforded a good tonnage of crushing-material. 

I At 100 ft. below the No. 6 level opening from the Queen of the May shaft the No. 4 
reef and the North-west have been cut in a crosscut from the Thames-Hauraki shaft. As far 
as explorations have proceeded here, both these veins show decrease in strength as compared 
with the upper levels, but they are still yielding pav-ore. 

The St. Hippo or Nana reef outcrops in the Collarbone Gully, where it follows the foot- 
wall of the Moanataiari fault for a considerable distance. This vein from certain blocks in 
the adit-workings gave a fair tonnage of ore, worth about 1 oz. to the ton. To further test 
its value in depth a crosscut was extended from the May Queen No. 5 level workings. The 
nuiin fault was intersected at a point about 1,750 ft. east-north-east of the shaft, and the 
St. Hippo reef, still closely associated with the foot-wall of the fault, was encountered. The 
veinstone here varied from 3 ft. to 10 ft. in width, but afforded no pay-ore. 

• C.-3, 1894, p. 62. 
8— Thames. 



114 

The future prospects of the May Queen Claim depend primarily on the results to be 
attained from exploiting the various veins at the deeper levels. Only the systematic 
opening-up of the country ^^■\\\ finally determine the value of the various veins existing at 
these lower horizons. Considerations, however, of the geological structure of this area and 
of the results of upper-level mining point to the conclusion that the more productive deep-level 
ground of the May Queen Mine lies to the west and south-west of the Thames-Hauraki shaft. 
The company are contributing to the joint deep-level development scheme, and are also open- 
ing out on the south-east side of the shaft at the 1,000 ft. level with a view to intersecting 
the Queen of Beauty and other reefs. 

STiortland Flat Claim {axQa, 100 acres; owners, an Auckland-Thames syndicate). — The Short- 
land Flat Claim includes a considerable area of the low-lying ground upon which the Short- 
land Section of the Town of Thames is built, also a neighbouring portion of the terrace country 
known as Block XXYII. On its northern and eastern boundaries it adjoins the May Queen 
and the Vanguard claims respectively. Former holdings Mng within its Umits are the 
Thames - Hauraki Extended Claim and pai"t of the Deep Sinker Claim. 

The underground workings are of hmited extent. A shaft (known as the Deep Sinker), 
12 ft. by 8 ft., ^\^th a collar-elevation of 25 ft., was sunk to a depth of 462 ft. by the Standard 
Exploration Company, London. From this shaft, a level — the Deep Sinker crosscut — open- 
ing at 450 ft. has been carried northward to and beyond the Shortland Flat - Vanguard 
boundary, that portion of the level lying within the claim under re\aew measuring 1,050 ft. 
The shaft is ecjuipped with a 10 in. plunger and draw-Uft pump and a winding-plant. The 
shallow workings include part of the South British adit, which enters the terrace country at an 
elevation of 28 ft. 

The surface of this claim is entirely covered with alluvial deposits (Pleistocene and 
Recent), and even at a depth of 400 ft. below sea-level consolidated andesitic rocks appear to 
constitute only a triangular-shaped area of about 11 acres out of the sum total of 100 acres. 
As greater depth is attained, this triangular area will, however, gradually increase, as the 
Beach " slide " which determines the south-western hmit of the f olid country — the Central 
block — dips south-west at angles approximating 45°. At a depth of 1,000 ft. the area 
enclosing consoUdated country rock may thus be approximately 20 acres. 

The andesitic rocks of this claim may be considered the downthrown counterpart of the 
flow and breccia complex forming the Una Hill area, and are separated from the latter by the 
Moanataiari fault, which has here a vertical displacement certainly exceeding 600 ft., and 
probably approaching 1,000 ft. This fault, assuming it to have a dip of 45°, enters the area 
at a depth of about 1,300 ft. below sea-level. The " Premier " andesite flow, which persists 
from the Kuranui to the May Queen, is quite unUkely to exist in the Shortland Flat area 
within the vertical limits of practical mining, if, indeed, it exists here at all. 

The value of the property is entirely a speculative one, as the ground is practically unpro- 
spected. Three parallel veins were intersected in the South British adit level, and vertically 
below in the crosscut, projected from the Deep Sinker shaft they appear to be represented 
by a series of small parallel veins extending over a distance of 165 ft. The counterpart of 
some of the more persistent of the Una Hill veins may be inferred to exist in the property, and, 
judging by conditions in the claims further northward, veins, which cannot be correlated with 
any of those on the upland side of the Moanataiari fault, are also'^Ukely to be found. 

It was the intention* of the former owners — the Standard Exploration Company — to 
drive a level to connect the Thames-Hauraki shaft with the Deep Sinker shaft of this property, 
The distance between these points is 2,250 ft., and of this 1,350 ft. lies within the area at 
present held by the May Queen Company. The co-operation of the two proprietaries is 
therefore advisable if a deep-level prospecting and drainage crosscut is to be driven in this 
direction. 

* C.-3, 1898, p. 57. 



115 

Vanguard Claim (area, 65 acres and 31 perc-hes ; owners, the May Queen Gold-mining 
Company). — The Vanguard Claim is confined to the high-level terrace country of 
Block XXVII, the surface elevations of which vary from 25 ft. to 160 ft. Adjoining claims 
are the May Queen, the May Queen Extended, the New Dart, and the .Shortland Flat. 
Former holdings within its boundaries are portions of the South British, Queen of Thames, 
Young Queen, and Loyalty. 

The underground workings are of limited extent. The deepest explorations consisted of an 
extension of the 450 ft. level crosscut from the Deep Sinker shaft of the Shortland Flat Claim. 
A shaft (collar-elevation, !)0 ft.) was also sunk to a depth of about 40 ft. in the northern end 
of the property, alongside the Karaka Creek Road, but operations here were abandoned at an 
early stage. Of the adit levels, the South British crosscut is probably the most extensive. 

The country rtck of the Vanguard (underlying the ten-ace gravels) is essentially the same 
as that of the Una Hill area to the eastward and the Shortland Flat area to the westward 
— interbedded andesitic tuffs, breccias, and flows, which in their altered state exhibit a marked 
purplish-grey colour. The Moanataiari fault has been intersected in the northern end of the 
Vanguard crosscut (440 ft. below sea-level), and from this point southward may be considered 
at this horizon to follow approximately the hue of the Water-race Reserve, which marks the 
eastern boundary of the claim. 

Several quartz veins have been intersected in that part of the Deep Sinker crosscut wliich 
traverses this claim. These, according to Mining Reports,* varied in width " from 6 in. to 
10 ft., and some of the quartz carried excellent mineral, but no gold was seen in breaking 
it out." The heavy flow of water encountered on cutting the Moanataiari fault in tliis level 
overtaxed the capacity of the Deep Sinker pumping-plant, and caused the premature abandon- 
ment of prospecting-work on these reefs. In the shallower workings three approximately 
parallel veins were cut in the South British adit. It may be stated that the veins cut in 
both the South British and Deep Sinker crosscuts are all on the hanging-wall or seaward side 
of the Moanataiari fault. The history of mining in the claims further northward has shown 
that the veins traversing the country seaward of this great fault have usually proved much 
more productive than those traversing the country on the upland or foot-wall side. So far, 
however, the limittid amount of prospecting-work done in the \'anguard Claim has proved 
unproductive, while the shallower adits in L'na Hill (the contiguous upland area) have 
afforded a considerable amount of gold. 

As far as doeper-level development is concerned, the general remarks made in connection 
with the adjoining Shortland Flat are equally applicable to the Vanguard. It will, however, 
be recognistni that at the 1,000 ft. level the Moanataiari fault will occupy a median position 
in the Vanguard property, so that " country " rock, referable to two very different geological 
horizons, will hero form the eastern and western portions of the claim respectively. 

Thames Deep-levels Consolidated Claim (area, 100 acres; owners, private individuals). — This 
is a foreshore claim which lies immediately to the southward of the Goods Wharf, and adjoins 
portions of the Victoria and Saxon claims. It has never been worked. No rocks excepting 
unconsolidated alluvium can be expected to exist in this property at and above a horizon of, 
say, 8W ft. below sea-level. In the vicinity of the depth specified, however, andesites of the 
Central block, bounded by the Beach "slide," which dips seaward at angles approxi- 
mating 4-5°, enter a portion of the claim from the eastward. Thus, at the l,(XX){t. level an area 
of andesitic rocks, measuring about 201) ft. in width, is probably available, and this should 
include certain of the Saxon and Victoria companies' reefs on their seaward strike. 

The depth at which the consoUdated rocks of the downfaulted Seaward block may be 
considered to exist is also a matter which concerns this claim as well as the north-western 
section of the Victoria Claim. This question is discussed in other sections of the report. 
(See pp. 70, 123-4.) 

*C.-3. 1907, p. 18. 
8'— Thames. 



116 



CHAPTER VII. 



SUMMARY OF THE MINERAL RESOURCES OF THE THAMES SUBDIVISION. 



rage 
Metalliferous Deposits other than Gold-Silver 
Veins . . . . . . . . 124 



Page 
The Future Prospects of Gold-SOver Mining. . 116 
(1.) The Future Prospects of Mining-areas 

outside the Thames Special Area . . 117 
(2.) The Future Prospects of the Thames 

Special Area . . . . . . 118 

(a.) The Upland Block .. ..119 

(6.) The Central Block .. ..120 Coal .. .. .. .. ..124 

(c.) The Seaward Block . . . . 12.3 



Stones for Building and Macadamising Pur- 
poses . . . . . . . . 124 



The mineral resources of the Thames Subdivision may be reviewed under the following 
headings : — 

The future prospects of gold-silver mining. 
Metalliferous deposits other than gold-silver veins. 
Stones for building and macadamising purposes. 
Coal. 

The Future Prospects of Gold-Silver Minixg. 

The goldfield of the Thames Subdi\asion. Hauraki, has since its discovery in 1866 up to 
the end of 1908 yielded from quartz reefs gold-silver bulUon to the value of £7,083,431. 

The various mining claims within the subdivision which have contributed to this out- 
put are contained within two more or less defined areas — one, the larger area, covering 
37 square miles, extending from Te Mata Valley in the north to the lower par-t of the Kauae- 
ranga Valley in the south ; and another, the smaller and less important, covering about one 
square mile, in the lower part of Puriri Valley. 

The geological formation with which the whole of the productive quartz reefs are associated, 
with the exception of a reef in the lower Tapu Valley and another in the Manaia Valley, are 
Tertiary andesites and dacites of the " First Period." It ^\^ll be observed that, according 
to the writer's mapping, the total superficial area occupied by these rocks in the subdivision, 
whether of proven auriferous character or otherwise, is not more than 63 square miles. The 
exceptions noted — Mclsaac's reef at Tapu, and the Victoria or Golden Hill reef at Manaia 
— occur in the basement stratified rocks (Tokatea Hill Series), which have but a limited 
development at the surface in the Thames Subdivision. 

In mining circles reference is not infrequently made to the undeveloped mineral wealth 
of the " backblocks of Thames." Presumably this term, as far as concerns the particular 
area under review, is applied to the relatively extensive watershed of the Waiwawa and the 
neighbouring watershed of the Kauaeranga above Mangaldrikiri Junction. In the writer's 
opinion, neither this belt of coimtry nor its continuation further southward into the Kiri- 
kiri, Wharehoe, and Matatoki valleys is ever likely to afford an extensive payably auriferous 
deposit. The rocks here consist mainly of Beeson's Island andesites, and to a less extent 
of younger rh3^olitic tuffs. The former are invariably characterized by extreme poverty 
of metallisation ; the latter contain only sparse local disseminations of the precious metal, 
and no defined fissure veins. 



117 

The above conclusion, based, on the character of the rocks, is supported by the rather 
desultory prospecting operations of the past forty years and by the prospecting-work carried 
on conjointly with this survey. If outcrops of older rocks — inliers of " First Period " ande- 
sites — could be shown to exist in this particular belt the prospects of mining would be poten- 
tially brighter. Although the writer's examination of this relatively extensive stretch of 
densely forested country failed to reveal such outcrops, the possibility of their occurrence 
may be conceded. 

The ascertained auriferous areas of the Thames Subdivision are therefore seen to be 
confined within fairly well-defined limits. 

In previous pages of this report the various vein-bearing areas have been subdivided 
for sake of convenience, and here again they may be reviewed under the following headings : 
(1) The future prospects of mining areas outside the Thames special area ; (2) the future 
prospects of the Thames special area. 

(1.) The Future Prospects of Mining Areas outside the Thames Special Area. — In connection 
with the future of mining in these outlying areas, the history of the past is likely to repeat 
itself. New discoveries may be expected from time to time, especially in or near those localities 
which have in the past yielded payable gold. The actual surface of the ascertained auriferous 
areas has been time and again searched by the individual prospector and the digger. It should 
be remembered, however, that a heavy overmantle of surface debris and a dense forest under- 
growth covers almost the whole of the country, and actual rock-exposures, except in the water- 
courses, are few and far between. The greater part of the area so covered has baffled the 
prospector and the digger. This ground is still available, but it is evident that more systematic 
and extensive operations will be required for its future successful exploitation. In connection 
with underground prospecting-work, it may be here stated that many a claim has been 
abandoned on poor results b)iug obtained from a limited amount of drifting on veinstone at 
one particular horizon. Since pay-ore on this field is frequently disposed in floors or zones, 
it should be recognised that the rise and the winze are even more important from a prospecting 
point of view than the drift. This is a fact which in many cases appears to have been over- 
looked. 

In the outlying areas of the. field very little systematic prospecting is at present in progress, 
and therefore the discovery of further auriferous veins, or of new ore-shoots in veins already 
located, is largely a matter of chance. 

Future mining exploration in the mineral belt extending from -Tapu to and south of 
Waiomo appears to offer fair prospects of meeting with success. The association of the gold- 
silver with sulphides of zinc, copper, and lead in portions of this belt renders special metal- 
lurgical treatment of the ores indispensable. Mill-costs on these sulphide ores are likely 
to be higher than on free-milling ores. As an offsetting advantage it may, however, be 
argued that systematically developed properties yielding auriferous sulphide ores usually 
maintain a more uniform and continuous output than those affording free-milling gold-quartz 
veinstone. In the latter class, which are on the Thames field the more common, the pay- 
ore, although in places attaining bonanza richness, is disposed as somewhat isolated pockets 
or shoots, the locating of which generally involves considerable time and expense. 

In the high comitry of Tararu Valley above Ohio Jimction the exploitation of the veins 
below their payable outcrop sections has, so far, proved unremimerative. It appears certain 
that the payable ores on the outcrops within the Scandinavian and neighbouring claims were the 
product of a superficial secondary enrichment of lean veinstone. The possibility of locating 
primary ore-shoots in the veins in the lower levels induces the expenditure of a limited amount 
of capital from time to time. At a somewhat lower elevation in this valley is the Vulcan or 
Eclipse reef, a strong vein of favourable characteristics which has in the past afforded a fair 
tonnage of pay-ore. The strength of the vein, and the belief that prospecting operations at 



118 

the lowest adit may liavo been prematurely abandoned, has led to further exploration being 
midertaken. 

The Otanui and the lower Puriri area, it may be remarked, still afford legitimate chances 
for further prospecting. 

(2.) The Future Prospects of the Thames Special Area. — The Thames special area — which 
extends from Tararu Creek and its tributary the Ohio to Hape Creek — has afforded a wonder- 
ful localisation of high-grade auriferous ores, and has been noted for the almost unparalleled 
richness of certain of its bonanza deposits. 

Gold to the value of about £6,750,000 sterUng has here been derived from an ai'ca cf 
country which measures not more than 6J square miles. Furthermore, perhaps 75 per cent, 
of this has been extracted from a sectioji of the area which does not exceed 200 acres. 

Almost the whole of the pay-ore of the field, whether derived from the adit levels pene- 
trating the hilly portion of the field or from the maze of workings projected from the various 
shafts opening up country below sea-level, has been derived from within 400 ft. or 500 ft. 
of the present land-surface. 

From the above remarks it would seem evident, even to the casual investigator, that 
forty years of continuous mining must have depleted the upper zone of this area of 6^ square 
miles, and more particularly that of the richer area, measuring only 200 acres, of by far the 
gTeater part of their pay-ores. This opinion being now generally held by experienced mining 
men of the field, money for investment in the further exploitation of the upper levels is becoming 
more and more difficult to obtain, and consequently the mining industry is not flourishing. 

It is not implied that further discoveries in the upper levels of the field may not be 
expected from time to time. Within the smaller area, which has proved the richer in the past, 
the discovery of the Waiotahi bonanza only some five years ago in a mine which had been 
continuously worked for the previous thirty years shows how difficult it is on a field of this 
character to say when even a certain horizon in a particular mine has been " worked out." 
In the larger area it can be affirmed, with reference to recent developments, that the belt of 
comitry enclosing the Waitangi, Watchman, and Sylvia claims is at the present time affording 
more hopeful prospects and attracting more attention than at any previous period. The 
complex character of certain of the ores has partly accounted for the retardation of mining- 
development in this quarter. It may also be remarked that for over a quarter of a century ' 
poor outcrop prospects led the miner to look with disfavour on the ore-bearing potentialities 
of the Waitangi- Watchman belt of comitry. 

With all due allowance, however, for the chances of fresh discoveries in the upper levels, 
and the profits which may accrue from the exploitation of ore-shoots now available, it will be 
readily admitted that something additional is required if the prestige of Thames as an im- 
poilant goldfield centre is to be maintained. 

The statement has frequently been made that the future progress of the Thames held 
would be in part effected by mining and milhng on a large scale the veinstone of several big low- 
gTade reefs which traverse the field between Moanataiari and Hape creeks, and which could 
be worked " water-free " for many years. The results of so-called trial crushings taken from 
different localities have been put forward in support of the argument. These test parcels, 
however, seem to have been far from representative ; and the fact remains that every systematic 
attempt made to treat at a profit vein-quartz blocked out from these large reefs beyond the 
circumscribed limits of local pay-shoots has resulted in failure. Mill-assays of the tailings 
have shown that the result would still have been far from profitable even if the whole gold- 
silver content had been recovered. 

A considerable amount of sampUng of these large veins was undertaken during the course 
of the writer's survey, both from outcropping portions and from cross-sections exposed in 
undergTound workings. The assays made have returned almost invariably a gold-content 



119 

of only ;i low grains to the ton. Those results further contirm the verdict proclaimed by the 
mill tests — namely, that the large reefs in question, apart from the local pay-shoots and the 
minor enrichments which occasionally occur at the intersections of small branching veins, have 
no value as ore-deposits. 

Wherein, then, does the hope of the Thames Goldfield he ? It may be stated that perhaps 
in no other quartz-reefing centre in the world with a record of upper-level mining paralleling 
that of Thames has less attempt been made to prove the deeper levels. It seems certain that 
only by a well-directed effort in this direction is there a hope of re-establishing the industry 
on the Thames Goldfield upon a satisfactory basis. 

In reviewing the prospects of deep-level mining in this centre prime importance may be 
attached to the fact that the area is divided by the Moanataiari fault and the Beach " slide " 
into what are geologically three separate blocks of country — (a) the Upland block, lying to the 
foot-wall side of the Moanataiari fault ; (b) the Central block, extending from the hanging- 
wall side of the Moanataiari fault to the Beach " slide " ; (c) the Seaward block, lying to the 
seaward side of the Beach " slide." The plans and sections accompanying this report show the 
position and extent of these three blocks and the probable disposition of the rocks involved 
in their structure. 

(a.) The Upland Block. — The Upland block, lying to the foot-wall side of the Moanataiari 
fault, constitutes by far the greater part of the Thames special area. It has been shown to con- 
sist of andesitic and dacitic flows and breccias resting upon stratified rocks of the Tokatea Hill 
Series (the " slates " of the miner). The approximate depth at which these old sedimentary 
rocks underlie the " auriferous series " in this block may be deduced from the fact that they 
outcrop at Rocky Point some 50 chains northward of Tararu Creek, and again have been 
encountered at a drilling-depth of 1,2-10 ft. (say, 1,170 ft. vertical) below sea-level in the bore- 
hole sunk by the Kuranui-Caledonian Company near the entrance to the Moanataiari tunnel. 
This old flooi-, irrespective of local irregularities which are almost certain to exist, may be 
assumed to dip southward at an angle of about 7°, as shown on the accompanying sections. 
The Upland block has from the upper levels yielded gold, and in places highly payable 
gold, from many different veins, but its \ield is not comparable with that of the Central block. 
The largest ore^deposit in the Upland block was that mined from the Old Alburnia Claim 
at an elevation of about 1,100 ft., and at a distance of some 60 chains from the foot-wall of 
the fault. Between this ore-deposit and the fault-line the Messenger's Hill area has on this 
line of section alone proved of considerable importance. Further southward the Una Hill 
area afforded very fair profits from mining operations in the shallower adits ; while in the 
north end of the field probably the Dunedin reef of the Day Dawn and Norfolk Claim yielded 
the best returns to the investors of bygone days. 

Irrespective of the elevations at which the various reefs outcropped, mining operations 
have proved unprofitable at greater depths than 500 ft. below the surface, and in many cases 
the pay-ores were found to terminate at even shallower horizons. 

Two ore-shoots at present being worked — namely, that of the Sylvia and that of the 
Waitangi claims respectively^present characteristics unlike any of the others heretofore 
mined at Thames. The former bears a complex sulphide ore, the latter a sulpho-tellmide ore ; 
and, as conditions of mineralisation have in each case been different from those which obtained 
at Thames generally, there is some hope that the vertical range through which these shoots will 
be found to persist may be greater than that of the usual type of the Thames bonanza ores. 
It may be remarked, -however, that the two claims mentioned have large available blocks 
un worked above the 5(X) ft. limit. 

The Moanataiari tunnel, which has been projected about a mile and a quarter from the 
foreshore to a point about 1,100 ft. below the outcrops of the Old Alburnia reefs, is the most 
extensive and deepest level penetrating the Upland block. Apart from the actual driving 
of the main adit with the offset crosscut extended from it into the Thames Claim, and the 



120 

main rise connecting the adit with the Sons of Freedom level of the Old Alhurnia workings, 
little pros^jecting-work has been carried out. On the whole, however, the prospects of meet- 
ing with another productive ore-bearing zone between this level and the upper workings are 
not promising. Below this adit, andesitic breccias may be inferred to replace the " Premier " 
flow andesite. Some indication of what may be expected at horizons deeper than that pene- 
trated by the Moanatairi tunnel will be afforded by the explorations on reefs intersecting 
similar breccias in the northern portion of the proposed 1,000 ft. level crosscut in the Central 
block. In the upper levels of the field the results of mining in the propylitised breccias — 
tlic " mottled country " of the miner — have rarely proved remunerative. 

(b.) The Central Block. — The Central block lies between the Moanataiari fault and the 
Beach " sUde." Judging by the data aiiorded by boring operations, together with a calcula- 
tion of the downthrow of the Moanataiari fault, the andesitic rocks may in the north end 
of the block be expected to persist to a depth of, say, 1,600 ft., before the floor of pre- Jurassic 
rocks (the " slates ") will be encountered. Further southward and to the westward of the 
Thames-Hauraki shaft it is not improbable that the andesitic rocks will be found to persist 
to a depth exceeding 2,000 ft., even if the possibility of crateral pipes which are thought to 
exist in this locaUty be left out of consideration. If, as is suggested by the disposition of the 
volcanic rocks in the southern end of this area and the abundant emanations of mine-gas 
in the foreshore mines, an old crater exists, say, southward of Waiokaraka Creek, the andesitic 
rocks will in this locahty extend to greater depths than those at which mining is practicable. 

The Central block has in the levels already exploited proved by far the most productive 
.area of the Thames Goldfield. Within its limits a belt of comitry measuring less tian 200 acres 
has yielded probably 75 per cent, of the total gold-yield of Thames, and has enclosed the 
great bonanzas known as the Shotover, the Moanataiari, the Caledonian - Golden Crown, 
the Cambria, the "Waiotahi, and the Prince Imperial. 

The history of mining thus proves that the Moanataiari fault, separating the Central 
block from the Upland block, has certainly in the upper levels exercised a very considerable 
influence in fixing the limits of the more highly productive portion of this field. It is beUeved 
by the writer that the initial formation of the Moanataiari fault fissure long preceded the last 
great downthrow of, say, 400 ft. along the fissure. This is inferred from the pecuhar be- 
haxaour of many of the veins in the proximity of the fault between the Waitangi-Dixon (?) reef- 
system and the Waiotahi-Cambria reef-system. If this contention is correct, the localisation 
of the remarkably rich groimd is probably due to more than the mere protection from denuda- 
tion of an upper zone of country by downthrow. It is hkely that the fault-plane determined 
two separate systems of ground-water circulation and consequently two separate areas of 
auriferous metalUsation. If a sectional plan is constructed showing the restoration of the 
Central block to the position it occupied before faulting took place no correspondence of the 
ore-shoots on the Seaward side of the fault ^\-ith those on the Upland side can be observed. 
It is probable, then, that the Moanataiari fault may again at the deeper levels Umit to the 
eastward the more productive vein-bearing coimtry. 

From what has been already stated it is obvious that the Central block is the one which 
should receive prime consideration in any initial scheme for testing the deeper levels of the 
Thames field. Proposals to open up this area at the 1,000 ft. level have been discussed time 
and again in mining circles ; but on this field, for some extraordinary reason, it has proved 
exceedingly difficult to give effect to a scheme necessitating the co-operation of the several 
proprietary companies. As far back as August, 1889, what was known as Mr. Alex. Brodie's 
scheme for developing the low levels was freely discussed and the necessary plans compiled 
by Messrs. Maclaren and Adams were pubhshed. As part of this scheme it was proposed to 
sink both the Queen of Beauty (Thames-Hauraki) and the Big Pimip shafts to a depth of 
1,000 ft., and to connect them by a crosscut. The proposal. to raise £100,000 to give effect to 



.121 

this and other extensive devolopmeut-works (iucludiug the extension of the Moanataiaii 
Tunnel, which has been recently carried out) did not meet with the necessary acceptance, 
and nothing was accompHshed. 

The sinking of the Thames-Hauraki shaft was undertaken by the May Queen Com- 
pany, with the assistance of the Dominion Government and the Thames municipal bodies, 
and completed in 1908 to a depth of 1,000 ft. (971 ft. below sea-level). This shaft holds a 
good position in the Central block, and from it, at the depth mentioned, the May Queen Com- 
pany is pushing a crosscut southward to intersect the Queen of Beauty and other reefs. The 
May Queen, Saxon, Victoria, Waiotahi, and Kuranui-Caledonian Companies now propose to 
co-operate in driving a main crosscut in a northerly direction to open up their respective claims 
at the same horizon. 

The special map accompanying this report is in great part a replica of the one prepared 
by Mr. E. F. Adams, and pubhshed in the Mines Reports of 1907. It shows the positions of the 
principal reefs, the Moanataiari fault and the Beach " slide " at the exploited levels, and also 
the computed positions of these reefs and faults at the 1,000 ft. level. It also shows the 
boundaries of the several claims. 

It will be noticed on comparing this map with the main i)lan of the area that many of the 
reefs of the upper levels cannot be expected to persist to the 1,0(X) ft. level, as they junction 
in dip above this horizon with certain of the larger fiattcr-lying reefs. It is not unlikely, how- 
ever, that reefs unknown in the shallower workings may be located at greater depths. 

The continuation of the Thames veins and ore-shoots in depth is, as Maclaren has re- 
marked,* "a matter that is indissolubly coixnected with the range of propylitisation of the 
andesites ; it is also dependent, though in a lesser degree, on the depth at which the floor 
of pre-Juiassic basement-rock may be encountered." 

The depth at which the floor of pro-Jurassic l)asemont-ro(k (the " slates ") is likely to bo 
encountered has been already considered. f 

In comicction with the range of propylitisatioji of the andesites, the question as to 
whether certain belts of comparatively little- altered or non-propyhtised andesito — "hard 
bars " — known in the upper levels may be expected to persist or to increase in size at gi eater 
depths, is a matter of considerable importance. Not only is crosscutting more expensive in 
this hard rock, but the reefs not infrequently terminate in it. or, if they do intersect it, are 
much contracted iji width, and almost invariably unprofitable. The most extensive bolt of 
this hard rock in the Central block is that extending south-eastward from near the foot-wall of 
the Waiotahi-Cambria reef in the Waiotahi Claim, through the Trenton Section of the New 
Moanataiari Claim, through the north-eastern portion of the Saxon Claim, and into the May 
Queen Claim. This belt follows fairly closely the hanging-wall side of the Moanataiari fault, 
and may be ex])octed to dip seaward with the hade of the fault. It is likely, therefore, that 
hard rock will encroach from the eastward on a considerable portion of a line drawn from the 
Thames-Hauraki shaft to the Kuraimi-Caledonian shaft at the l,(XK)ft. level. This, unfor- 
tunately, is the line of the proposed north-west crosscut adopted by the five combined com- 
panies. The narrower ribs or " hard bars," probably ofl'shoots from this more extensive belt, 
separate in the upper levels certain of the parallel reefs, among others the Queen of Beauty 
No. 1 reef from the Cardigan No. 2 reef, and the Prince Imperial No. 2 reef from the Mariner's 
reef. These are probably not so persistent, and in some cases may be found to cut out 
in depth. The western or seaward half of the Central block rather than the eastern portion 
is therefore likely at the deeper levels to afford the propylitic rock, or, to use the miner's term, 
the " kindly sandstone." 

The probability of encountering a considerable amount of hard rock in the proposed 
north-west crosscut at the 1,000 ft. level would have been avoided, or at least greatly minimised, 



* " Gold," 1908, p. 312 : J. Malcolm ilaclaren, D.Sc. + The prospects of flpep-lp%'ol mining in tho 

ba.sement-rocks — "the slates " — of Hauraki have been considered by the writer in the report on the adjoin- 
ing Coromandel Subdivision: Bulletin 4 (New Series), N.Z.G.S., j). 147. 



122 

In- piojcctiug tliu crosscut from tlie Tliames-Hauraki shaft to the Old Big Piunp shaft, via 
the Saxon shaft. This route would have afforded the additional advantage of almost longi- 
tudinally bisecting, at this level, the stretch of comrtry lying between the Moanataiari fault 
and the Beach " slide " — the Central block. It would, as indicated later, have passed near 
to what promises to prove the most productive line of the 1,000 ft. horizon, and would, further- 
more, have rendered less difficult the problem of efiecting satisfactory ventilation in an area 
subject to considerable emanations of mine-gas. 

The south-eastern crosscut driven by the May Queen Company at the l.UUOft. level 
from the Thames-Hauraki shaft penetrated a propylitised flow andesite for a distance of 
about 170 ft., at which point it is separated by a carbonaceous parting from a complex of 
alternating flows and breccias. The favourable country extending for 170 ft. in the direction 
indicated appears to be the downward continuation of the " Premier " flow rock which enclosed 
the bonanza zone of the more northerly portion of the field ; and this rock may be expected 
to continue north-westward of the pump shaft for a considerable distance. 

The vital question as to the piobabihty of pay-ores existing at any particular horizon 
in the area under review is also intimately connected with the vertical distribution of the ores 
in fairly definite floors or zones. The mining operations of the past have clearly demon- 
strated that within the Central block the payable ores and the included rich bonanza deposits 
were confined to a particular inclined zone. This zone outcropped in the vicinity of Shot- 
over Creek and Kurauui Hill. The Shotover bonanza itself was actually exposed in the bed 
of the creek named at an elevation of about 100 ft. above sea-level. From the Shotover the 
zone dips about south-south-west, and at a distance of 26^ chains from the locality named the 
most southerly of the bonanzas yet located was found in the Prince Imperial (Victoria 
Claim), between depths of 270 and 450 ft. below sea-level. The average thickness of this 
zone of pay-ores is difficult to assess, but it probably exceeds 400 ft. even in the northern and 
middle sections of the field. Many minor deposits of ore were obtained both above and below 
the somewhat indefinite Umits of this zone, but. as the nature of the country rock is not 
markedly different at these various horizons, these occuiTences are not remarkable. South- 
ward of the Piince Imperial, as the detailed description of the mines will show, a considerable 
amount of ores has been mined from the Saxon and from the Queen of Beauty ground. No 
bonanza deposits comparable with those of the northern portion of the field were, however, 
discovered in these claims, and it is not unlikely that remunerative gTOund lies below the 
levels exploited. The steeper plunge of the " Premier " andesite flow, as suggested by recent 
developments in the Queen of Beauty, may also imply a more pronounced plunge of the 
highly productive auriferous zone in the area south of the Prince Imperial. It may be stated 
that the best prospects obtained in the " 640 " ft. level, driven southward from old Big 
Pump shaft, were in its southern end. Here a favourable class of propylite was penetrated, 
and the Prince Imperial No. 2 reef pelded some stone showing visible gold. 

The arrangement of pay-ores in floors or zones in metalhferous veins is a feature of many 
mining districts besides Thames. Within Hauraki itself this is exhibited in the Talisman 
and Crown Mines at Karangahake, where mining operations have been extended through a 
vertical range of nearly 2,000 ft. 

It seems highly probable from the evidence available that it is with the downward 
continuation of the same zone of country that afforded the pay-ores of the upper workings 
that the 1,000 ft. level from the Thames-Hauraki shaft will be mainly concerned. Judging 
by the disposition of all the great bonanzas which have been located in the past, the 
ground commanded by the 1,000 ft. level, which gives promise of proving the more pro- 
ductive, lies to the west and south-west of a line connecting the Thames-Hauraki, Saxon, 
and Prince Imperial shafts. This stretch of country lies within the May Queen, Saxon, and 
Victoria claims. 

Northward of an east-west hue passing through the Prince Imperial shaft Hes the 
Waiotahi, Kuranui-Caledonian, and Kuranui claims, also part of the Victoria Claim, and most 



123 

of the New Moiiiiatciiiiri. The prospects of the whoh; of this areii iiro much move specuUitivc. 
Success implies the discovery of a second productive zone below the poor or barren zone 
penetrated in the " 640 " ft. crosscut. As to whether such a productive zone exists can only be 
determined by actual mining exploration. Reference is frequently made in this connection 
to the propyUte of favourable character penetrated by the Kuranui-Caledonian bore at a 
di-ilUnif-depth of about 1,030 ft., and to assays ranging from lis. 4d. to 13s. (id. per ton yielded 
by a sample of the rock seamed with quartz veinlets, which was taken from this horizon. 
Unfortunately, the boro at a short distance below this point appears to have passed out of the 
Central block, through the Moanataiari fault, and into the Upland block, so that nothing is 
known as to the vertical extent of this propylitic band. If it proves to be a productive zone 
it will probably be disposed approximately parallel to the upper one — that is, it will dip south- 
ward, and will therefore lie below the limits of the proposed 1.000 ft. level. 

It is more than likely, in connection with tliis northern section, that from suitaljle j)oints 
in the contemplated 1,000 ft. level workings the diamond drill will play an important part in 
initially testing the character of country below this horizon. Exploration by drilling is gene- 
rally condemned on this field. It is true that if a bore-hole is sunk with the sole object of 
locating payable veinstone on a bonanza goldfield. such as Thames, the rosidt is almost certain 
to bo counted a failure. If, however, an indication of the nature of country rock at deepet 
horizons is sought, diamond drilling judiciously carried out has nuich to recommend it, sincj 
on few fields does the existence of pay-ores show greater dependence on the character of the 
coimtry rock enclosing the veins than at Thames. It canjiot be gainsaid that the Kuranui- 
Caledonian borehole unquestionably justified the capital outlay, since it has thrown more 
light upon conditions obtaining at the deeper horizons of this portion of the Thames Goldfield 
than any other mining-work yet carried out. 

A considerable area included within the Central block exists to the south and south-east 
of the Thame.s-Hauraki shaft. Since this area lies to the dip of the main oro-bearing zojie 
already described, it must be considered to offer inducement for systematic development at the 
lower levels. That it consists altogether of a complex of flows and breccias is recognised ; but 
so also does its counterpart, the Uini Hill, in the Upland l)lock, which has yielded a lair 
amount of pay-ores. As Park pointed out in 1894,* the northern and middle divisions of the 
field have invariably given far better results from the hanging-wall side of the Moanataiari 
fault than from the foot-wall side. It is therefore fair to assume that deposits of pav-ores 
may bo yet located in this southern division, the vein-bearing rocks of which are in places 
overlain by a considerable depth of terrace gravels and more recent alluvium. 

(c.) The S("award Block. The Seaward block, a terra in(M<jnila, lies to the seaward side of the 
Beach ' slide," which forms the western limits of the Central block, and has since the earliest 
days of the Thames field been the subject of considerable speculation. From the preceding 
pages of this report it will bo observed that the weight of evidence is considered to favour 
the opinion that a great fault, with a downthrow exceeding that of the Moanataiari fault, 
exists here. What is now known as the Beach " slide " — an unconformity separating the 
andesitic rocks from the alluvium filling the Firth of Thames— is appariwitlv the eroded face 
of this fault-scarp. The Victoria bore sunk in this alluvium did not find bottom at a drilUng- 
depth of 1.12(tft. It is, therefore, quite unlikely that the proposed mining operations at 
1,000 ft. (971 ft. below sea-level) in the Central block can be extended into this Seaward block. 
A further attempt to tost by boring the character of the consolidated rocks of this block, and 
the depth at which they underlie the alluvium, is desirable, as the possibility is by no means 
remote that there exists here a faulted counterpart of what has proved the richest portion 
of the Thames Goldfield. 

* 0.-3, 1894. 



124 

As to whether this dowii-faultod block lies Avithiii the vertical limits at which mining Is 
practicable on this field of relatively high temperatnxe-increment and abundant gaseous emana- 
tions remains to bo proved. 

Metalliferous Deposits other than Gold-Silver Veins. 

Metals other than gold-silver bullion exported from the Thames Subdivision consist 
of lead, copper, and zinc contained in certain auriferous concentrates which have been shipped 
to Australia for smelting-treatment. These concentrates were derived from the ores of the 
Monovvai and Comstock veins at Waiomo, the Sylvia vein at Tararu, and the Waitangi vein, 
Shellback Creek. Further shipments of such concentrates are to be expected from time to 
time, but the ores are essentially gold-silver ores, and the value of the baser metals is rela- 
tively low. 

Mercury-bearing ore (cinnabar) occurs in the Mangakirikiri Valley, Kauaerauga, but so far 
prospecting operations have failed to locate any payable deposit. The workings that had 
not collapsed were examined, and the cinnabar was observed to occur in isolated pockets in 
a nearly flat-lying narrow band of chalcedonic quartz enclosed in altered andesite. The 
prospects of discovering a payable deposit do not seem bright. 

Stones for Building and Macadamising Purposes. 

The aiidesites throughout the area are so closely and so irregularly jointed that even 
the hard and unaltered rock is unsuitable for building-sfone. Furthermore, andesitic rocks 
in general are Jioted for their lack of rift, thus rendering dressing both difficult and expensive. 

Tufaceous and massive rhyoUtes are found in the upper Kauaerauga Valley. Some of 
these, had they occiUTed in less inaccessible locaUties, might have been used for certain con- 
structional purposes. 

For macadamising reads the hard, unaltered andesite " blue-metal " is the rock generally 
used throughout the district. Rock suitable for such purposes is fairly abundant, but the 
locaUty of an outcrop is the main factor in assessing its value. The occasional crosscutting 
of the " hard bars " in the foreshore mines affords some fairly good rock, which, can be cheaply 
handled. 

Coal. 

The New Zealand coal-bearing strata, which have a very limited development in the 
Coromandel Subdivision, do not occur in the Thames area. 

The discoveries of coal which have occasionally been reported are referable to the irregular 
unconformities — the old land-surfaces — which separate the volcanic rocks of different ages. 
Such coaly strata occur in Mill Creek (Whitianga), and at the head of the Kauaeranga, Wai- 
wawa, Mata, and Puru streams ; but from the very nature of the deposits they can have little 
or no economic value, except perhaps for limited use if required in the actual vacinity of their 
outcrops. 



125 



APPENDICES. 



LIST OF ELEVATIONS OF THE PRINCIPAL MINE-WORKINGS OF THE THAMES 

SPECIAL AREA. 



[+ = Above sea-level. 


- 


= Below sea-level. (a.) = Approximate.] 






Saxon Claim — 




Ft. 


1 Kuranui-Caledonian Claim- 




Ft. 


Saxon shaft-collar 


. + 


6 


Caledonian shaft-collar 


-t- 


91 


„ No. 1 level 


— 


100 


„ No. 1 level 


-- 


116 


„ No. 2 „ 


— 


171 


No. 2 „ .. 


— 


171 


„ No. 3 „ 


_ 


241 


No. 3 , 


— 


261 


„ No. 4 „ 


— 


311 


No. 4 „ .. 


— 


376 


„ No. 5 ,. 


. -- 


377 


Poverty and Charleston upper 






„ No. 6 ,. 


. — 


446 


level (a) . . 


+ 


1(K) 


Exchange shaft-collar . . 


. -1- 


17 


Poverty and Charleston low 






„ crosscut 


. — 


150 


level (a) . . 


+ 


40 


Victoria Claim — 






Albion shaft-collar 


+ 


23 


Prince Imperial shaft-collar 


. + 


7 


„ 188 ft. level . . 


— 


166 


„ No. 1 level 




81 


Junction main shaft^ — 






No. 2 „ 


_ 


137 


100 ft. level 


+ 


219 


No. 3 .. 




237 


200 ft. level (a) 


+ 


119 


No. 4 ., 




326 


All Nations shaft — 






No. 5 ., 




H4 


150 ft. level 


+ 


166 


No. fi .. 




485 


200 ft. „ 


H- 


115 


No. 7 .. 




.555 


Glasgow shaft 150 ft. level 


+ 


97 


Tookey's shaft-collar . . 


. -1- 


31 


Hazell)ank shaft-collar. . 


-t- 


89 


KM) ft. level . . 




(iX 


Belfast main level . . 


-1- 


38 


140 ft. „ .. 




109 


Kuranui No. 1, Hazelbank 






210 ft. „ .. 




170 


level 


~ 


51 


300 ft. „ .. 


" 


259 


Intermediate level, near Hazol- 






400 ft. „ .. 




385 


i bank shaft 


— 


121 


Old Big Pump collar . . 


. + 


15 


(Kuranui No. 1), No. 1 Inter- 






„ No. 1 level 





67 


mediate 


— 


146 


400 ft. ,. 


_ 


385 


No. 2 Inter- 






640 ft. .. 




625 


mediate 


— 


195 


Waiotahi Claim — 






Otago and Golden Calf shafts, 












level connecting 
Red Queen shaft, crosscut 


_, 


116 


Waiotahi shaft-collar . . 


-j- 


62 














24 


No. 1 level 
No. 2 „ . . 


— 


57 
124 


Moanataiari tuimel (entrance) . . 
Kuranui Claim — 


-f 


26 


„ No. 3 „ .. 


. — 


194 


Shotover shaft-collar . . 


-f 


98 


„ No. 4 „ .. 


. — 


260 


Kuranui tunnel 


-1- 


23 


„ No. 5 „ .. 


. — 


319 


Shotover. 74 ft. level . . 




50 


No. 6 ., .. 





366 


1 1 












„ level 


+ 


127 


From Golden Crown shaft — 






May Queen Claim — 






Nos. 1 and 3 levels . . 


. — 


57 


Queen of the May shaft-collar . . 


+ 


93 


No. 4 (100 ft. level) .. 


. — 


127 


No. 2 level . . 





171 


No. 2 shaft— No. 2 level 


. — 


171 


No. 3 „ .. 





243 



126 



iviay i^uecn uiaim — conlmuea. 




Ft. 


Queen of the May No. 4 level . 


. — 


318 


^ No. 6 „ . 


. — 


450 


No. 7 „ . 


. — 


507 


May Queen No. 3 level 


. — 


324 


No. 4 „ 


. — 


425 


„ No. 5 „ 


. — 


533 


No. 6 „ 


. — 


628 


Queen of Beauty shaft-collar 


. -1- 


29 


„ No. 1 level . 


. — 


110 


No. 2 „ . 


. — 


174 


No. 3 ,. . 


. — 


238 


No. 4 „ . 


. — 


305 


„ No. 5 ,, 


. — 


356 


No. 6 ., . 


. — 


423 


No. 7 „ . 


. — 


483 


No. 8 „ . 


. — 


521 


No. 9 „ . 


. — 


577 


No. 10 „ . 


. — 


648 


No. 11 „ . 


— 


728 


1,000 ft. level (A 


) - 


971 


City of London shaft-collar 


+ 


65 


,, No. 1 level 


— 


125 


No. 4 „ 


— 


283 


No. 5 „ 


— 


345 


No. 6 „ 


— 


410 


Bird in Hand shaft-collar 


-f 


16 


No. 2 level 


— 


147 


No. 3 „ 


— 


200 


No. 4 „ 


— 


267 


Old shaft west of Nana No. 4 leve 


1 + 


190 


St. Hippo drive, on Nana reef . 


-h 


245 


Nana shaft . . 


-t- 


300 


Lone Hand Section — 






Adelaide No. 2 level. . 


-f 


272 


Moa tunnel 


+ 


242 


Rocky Point level (Adelaid< 






No. 3 low level) 


+ 


153 


Vanguard Claim — 






Success level . . 


+ 


96 


.Vanguard shaft (new) collar 


+ 


90 


,, surface drive 


+ 


86 


South British tunnel . . 


-1- 


28 


Deep Sinker main crosscut 


— 


440 


Shortland Flat Claim — 






South British tunnel . . 


+ 


28 


Deep Sinker shaft-collar 


+ 


25 


,, main crosscut 


— 


440 


New Moanataiari Claim — 






Just in Time shaft-collar 


-f 


148 


„ No. 1 level 


— 


110 


No. 2 „ 


— 


169 



New Moanataiari Claim — continued. 

Just in Time; No. 3 level . . — 

No. 4 „ . . - 

Cambria shaft-collar . . . . -I- 

No. 2 level 

„ No. 3 „ 

No. 4 „ 

South-west from Moanataiari shaft- 

80 ft. level 

150 ft. level 

Nonpareil shaft-collar . . -|- 

„ adit . . . . -f- 

,, low level . . . . -I- 

,, long tunnel . . + 

Golden Calf shaft-collar . . -i- 

,, upper level . . — 

,, low level . . . . — 

Golden Calf shaft to Otago shaft, 

No. 1 level . . . . — 

Golden Calf shaft to Moanataiari 

shaft, No. 1 level 
Central Italy shaft-collar 
,, No. 1 level 

No. 2 „ 
No. 3 .. 
Shaft east of Central Italy shaft. 

No. 2 level . . . . + 

Shaft east of Central Italy shaft. 

No. 3 level 
Redan crosscut 
No. 1 Reef-drive 
Old Alburnia Claim — 
Papakura drive 
New Alburnia shaft-collar 
Papakura intermediate level (a 
Eldorado upper level . . 
Ruby low level 
Nebraska level 
New Alburnia surface level 
Bendigo Independent level 
Dixon's middle level 
No. 1 or Intermediate, near S^ 

of Freedom 
Bride of the West level 
Eldorado low level 
Rose and Shamrock level 
Mahurangi drive 
New Alburnia battery level 
John o' Groats upper level 
Whau level . . 
John o' Groats middle level 
" 70 ft." level (near Nebraska drive) -f 



Ft. 
253 
352 
203 
31 
91 
141 

50 
120 
338 
183 

82 
27 

231 
72 

121 

116 



— 


120 


-1- 


277 


-h 


72 


+ 


12 





53 



12 



— 


53 


-H 


150 


-H 


461 


-1- 


1.201 


-H 


1.170 


-f- 


1,135 


-1- 


1,103 


-1- 


1,075 


-f 


1,062 


+ 


1,051 


-t- 


1,023 


-f- 


1,010 


-1- 


1,000 


-1- 


1,000 


-1- 


985 


-t- 


969 


+ 


950 


+ 


933 


-\- 


879 


-f- 


869 


+ 


840 


+ 


806 



127 





Ft. 


+ 


800 


+ 


780 


+ 


769 


+ 


765 


+ 


761 


+ 


760 


+ 


760 


+ 


736 


+ 


731 


+ 


727 


+ 


714 


+ 


714 



+ 700 



700 



+ 669 



663 



Old Albuinia Claim — continued. 
Soils of Freedom - Flying Cloud 

drive (a) . . 
New Whau Section — 

Upper drive on Waikato reef (a) 

Drive on reef (a) 
Flying Cloud low level 
John o' Groats low level 
Sons of Freedom — shaft-workings 

(A) 

Black Angel No. 2 level (a) 
Lincoln Castle drive 
Drive on Berkeley Castle reef 
New Whau, Section — 

No. 1 level on reefs No. 1 
* and 2 

Christchurch Company's tunnel 
New Alburnia 160 ft. level 
New Whau, Daughters of Freedon 

level 
New W'hau and Sons of Freedom 

40 ft. level . . 
New WTiau No. 2 level, reefs 

and 2 
New WTiau and Sons of Freedom 

90 ft. level . . 
New Whau and Sons of Freedom 

150 ft. level 
Berkeley Castle main adit 
Watchman low level . . 
Unicorn low level 
Sons of Freedom level . . 
23rd June level 
Middle Star low level . . 
New Whau, Caliban crosscut 
Moanataiari Section upper drive 
Drive on West Coast reef 
Lion upper drive 
New Whau, Alfred top level (a) . 
Moanataiari Section — 

No. 3 level 

Drive on Teasdale vein No. 1 (a 
Dauntless low level 
New Wliau, Alfred low level 
Moanataiari Section, Teasdale vein 

No. 2 (a) .. 
Point Russell leve! 
Lion shaft-collar 
Lion crosscut 
Moanataiari 100 ft. level 
Moanataiari main tunnel at Al- 
burnia rise . . . . . . + 84 



-1- 


614 


+ 


596 


+ 


593 


+ 


579 


+ 


559 


+ 


556 


+ 


536 


+ 


510 


+ 


510 


+ 


463 


+ 


463 


+ 


440 


+ 


432 


+ 


397 


+ 


396 


+ 


361 


+ 


307 


+ 


295 


+ 


279 


+ 


266 


+ 


215 



West Coast Claim — 




Ft. 


West Coast tunnel 


. -f 


480 


„ short drive (a) 


. + 


380 


,, long drive 


. + 


300 


Thames Claim — 






Hauraki Golden Age No. 2 level, 




Fearnought reef 


. + 


1,051 


Hauraki Golden Age — 






No. 1 level . . 


. + 


1,022 


No.3 „ 


. + 


1,000 


Waterfall drive 


. -H 


976 


No. 2 level 


. + 


954 


No. 3 level, Hopeful 


. -1- 


885 


Australasian low level 


. + 


719 


Erromanga level 


. + 


686 


Cosmopolitan drive 


. -1- 


678 


Golden Cup level 


. 4- 


596 


Watchman low level 


. + 


593 


Nonpareil drive on No. 2 reef 


. -1- 


580 


Euston level . . 


. + 


580 


Unicorn low level 


. + 


579 


Nonpareil, drive en Wade reef (a) 


-f 


552 


Hauraki Golden Age — 






Intermediate level (a) 


. -1- 


540 


Balmoral level 


. -f 


.502 


Harp of Erin drive 


. -f- 


486 


Hauiaki (Jokhni Age, Diggers' 




Friend level (a) 


. -t- 


430 


Nonpareil drive on Queensland 






reef (a) . . 


. -H 


405 


Beehive Lead drive 


. -1- 


380 


Hauraki Golden Age, low level 




drive on foot-wall 


. -1- 


.371 


Nonpareil, Liverpool Boya' drive 


) 




(A) 


. -t- 


3.50 


Point Russell level 


. -1- 


295 


Thames crosscut from Moanataiari 




tunnel (a) 


. -1- 


55 


Middle Star low level . . 


. -f 


536 


AlfriKl level . . 


. + 


.361 


Reliance Claim — 






No. 3 level (partly iji Caspian) . 


. -f 


1,0.36 


Bendigo Independent level 


. -1- 


1,023 


Eldorado low level 


. + 


985 


Bendigo Independent low level . 


. -H 


981 


Orlando top level 


. + 


806 


,, intermediate level 


. + 


720 


Goldfinch level 


. + 


715 


Norwegian level 


. + 


621 


Golden Drop Claim — 






Deeside low level 


. + 


1,355 



128 



Magnet Claim- 




Ft. 


Bank of New Zealand low level . . 


+ 


1,420 


Multum in Parvo low level 


+ 


1,413 


Mocking Bird level (a) . . 


+ 


1,320 


Southern Pacific level . . 


+ 


1,312 


Vale of Avoca low level (a) 


+ 


1,230 


Magnet low level 


+ 


816 


Day Dawn and Norfolk Claims — 






Norfolk No. 2 level (a) 


+ 


575 


Sunbeam drive (a) 


+ 


540 


Sunbeam low level (a) . . 


+ 


440 


Dunedin top level (a) . . 


+ 


430 


Norfolk No. 3 level (a) 


+ 


430 


Day Dawn (a) 


+ 


364 


Norfolk intermediate level (a) . . 


+ 


348 


Eoyal Charter level (a) 


+ 


342 


Day Dawn intermediate level (a) 


+ 


335 


280 ft. level (a) 


+ 


330 


Day Dawn low level (a) 


+ 


295 


Tararu Creek 210 ft. level (a) . . 


+ 


260 


„ No. 2 intermediate 






level (a) 


+ 


255 


Wild IVIissouri level 


+ 


228 


Tararu Creek No. 1 intermediate 






level (a) . . 


+ 


188 


Dunedin low level (a) . . 


j- 


158 


Tararu Creek battery level (a) . . 


+ 


40 


Watchman Claim — • 






Low level 


+ 


700 


Sylvia Claim — 






Kaiser crosscut 


+ 


865 


„ "New Find" .. 


+ 


845 


,, Eaglehawk drive 


+ 


786 


Sylvia shaft-collar 


+ 


762 


„ Taylor's top level 


+ 


718 


„ ,, low level 


+ 


668 


,, old low level 


+ 


548 


New Sylvia low level . . 


+ 


434 


Bonanza Claim — 






Bonanza drive (Shellback) 


+ 


236 


Waitangi Claim — 






Upper level (No. 3) . . 


+ 


486 


No. 2 level (Slam) 


+ 


370 


Low level (No. 1) 


+ 


248 


Southern Queen Claim — 






Karaka Mines — 






Drive F . . 


+ 


1,184 


Drive E . . 


+ 


995 


Onehunga reef 


+ 


900 


Drive D (a) 


+ 


830 


Drive C . . 


+ 


624 1 



Southern Queen Claim — continued. 
Karaka Minos — continued. 
Drive on reef B 
Crosscut 

Drive on reef A (a) . . 
Atlantic crosscut 
Savage's upper level (a) 
Tunnel level (a) 
May Queen Extended Claim — 
Adelaide No. 1 level (a) 
Adelaide and Lone Hand inter- 
mediate level 
Adelaide No. 2 level . . 
Loyalty drive 

Rocky Point level or Adelaide 
No. 3 level . . 
New Una Claim — 
Duke's No. 1 level 
„ No. 2 „ 
„ No. 3 „ 
Una No. 2 level 

„ No. 3 „ 
Mackenzie's upper level 
Hardman's level 

Adelaide and Lone Hand inter- 
mediate level 
Flora McDonald level (a) 
Una No. 4 level 
Pride of Karaka No. 1 
Loyalty drive 
Rocky Point or Adelaide No. :' 

level 
Success level . . 
Occidental Claim — 
North Star upper level 
No. 2 level 
Una No. 4 level 
Lord Nelson No. 2 Claim — 
North Star upper level 

,, ,, (another) 



New Dart Claim — 

Dart shaft-collar 

,, No. 2 level 

„ long adit 

,, No. 3 level 

„ No. 4 „ 

Fortuna No. 1 level (a) 

„ No. 2 „ (a) 

„ No. 3 „ (a) 



Ft. 



+ 


587 


+ 


559 


+ 


550 


+ 


479 


+ 


450 


+ 


360 



+ 340 



4- 


283 


+ 


272 


+ 


178 



+ 153 



-t- 


696 


-1- 


626 


+ 


587 


+ 


453 


+ 


372 


+ 


336 


+ 


298 


+ 


283 


+ 


250 


+ 


246 


+ 


200 


+ 


178 


+ 


153 


+ 


96 


+ 


590 


+ 


494 


+ 


246 


+ 


590 


+ 


580 


+ 


560 


+ 


192 


+ 


62 


+ 


15 


— 


8 


— 


78 


4- 


250 


4- 


200 


-1- 


100 



TABLE OF GEOLOGICAL FORMATIONS COMPARED WITH THOSE OF PREVIOUS WRITERS. 



COX, 1882. 



Lower Carboniferous and Upper 
Devonian — 
Slatep, sandstones, and felsites. 



Cretaceo-Tertiary — 

Coal-bearing series of Cabbage Bay. 



Age Dodbtfdl — 

Auriferous rocks of the Thames. 
Breccias and tuf!s. 



Lower Miocene — 
Trachytio breccias. 



Pliocene— 
Rhyolite formation. 



PARK, 1897. 



Pal/Eozoic (Probably Devonian) * — 
Slaty shales and grauwackes 
(gold-bearing). 



Lower Eocene — 

Marine limestone, marly sand- 
stones, and conglomerates with 
brown coal. 



Upper Eocene — 

Andesitic lavas, tufff^, and 
glomerates (gold-bearing). 



Miocene — 

Andesitic breccias and tuffs. 



Pliocene — 

Rhyolitic lavas and tuSs. 



Pleistocene — 

High-level gravel terraces. 



Recent — 

River-flats, swamps, and blown 
sands. 



MACLAREN, 1900. 
(Refers to Coromandel mining centre only.) 



Carbonipbrods (Maitai Slates 
OF Hochstetibb) — 
Slaty shales, grauwackes, sand- 
stones, crushed breccias, fel- 
sites, and felsitio tuffs. 



Lower Eocene — 

Clay marls, slate conglomer- 
ates, foraminiferal limestones, 
with small coal-seams. 



Upper Eocene or Oliqocene — 
Andesites (augite and horn- 
blende), fresh and decomposed, 
fine-grained tuf^s. 



Miocene — 

Trachytic and andesitic aggh 
merates, breccias, and dykes. 



[The Pliocene acidic rocks do 
not occur in the area mapped by 
this writer.] 



Pleistocene — 

River-terraces, lacustrine beds. 



Recent — 

Alluvial flats, harbour-muds, 
swamp-deposits. 



McKAY, 190.5. 



Te Anau Series (Uppee Devonian)-- 
Stratified beds of igneous material with 
associated eruptive and dyke rocks. 



Maitai Seeibs (Lower Carboniferous) — 
Sandstones, slaty shales, and mudstones, 
with intruded dyke rooks. 



Wairoa Series (Thiassic) — 

Sandstones and conglomerates formed of 
igneous rocks, and slate sand muds tones. 



/ Lower or Coal-bearing Series — 
Conglomerates, sandstones, and 
shales with coal. 



Middle and Upper Beds — 

Marly greensands with concretions, 
compact limestones and calca- 
reous sandstones. 



Thames-Tokatea Group — (Eocene) (?) — 

Eruptive matter, mostly andesitic flow 

rocks, and breccias, &o., out by dykes. 



Kapanga Group (Upper Eocene) — 
Same as above. 



Bbeson's Island Group (Miocene) — 
Eruptive matter wholly andesitic or da- 
citic ; stratified tuff beds with coal. 



f (rt.) Older Rhyolites — 
(6.) PuMiCEODS Agglomerate or 
Whitianga Beds — 
Bieccia agglomerates mostly of acid 
rocks, pumiceous sands, &c., with 
beds of lignite. 



(c.) Middle Rhyolites — 
Massive flow and intrusive rocks, for 
most"part resting on (6). 



(d.) Younger Rhyolites — 

Brecciated or pitchstone rhyolites 
chiefly developed in the upper 
basin of the Ohinemuri watershed. 



Raised Beaches (Post-Pliocene) — 
Coarse beaob-gravels, chiefly along west 
side of the peninsula. 



Alluvial (Post-Pliocene)— 

Coarse gravel, river-deposits, and finer 
sediments. 



Classification in Coromandel Bulletin. 
(Eraser and Adams, 1907.) 



Tokatba Hill Series— 

Argillites and grauwackes, with in- 
terstratified beds of igneous ma- 
terials. 



MoBHAU Series — 
Argillites and grauwackes. 



Manaia Hill Series (Jurassic) — 

Argillites, grauwackes, grits, and fine 
conglomerates. 



Torehine Series (Lower Eocene) (?) — 
(a.) Conglomerates, sandstones, and 

shales with coal-seams. 
(6.) Marly sandstones, calcareous sand- 
stones, limestone. 



Tertiary Volcanic Rocks op 
the "First Period" (Upper 
Eocene) (?)— 

Acidic : Rhyolitic tuffs. 

Semi-basic : Andesitic and dacitic tuffs, 
breccias, and lava-flows. 



Classification in Thames Bulletin. 
(Eraser, 1910.) 



Tokatba Hill Series (Pre-Jurassic) — 
Argillites and grauwackes, with inter- 
stratifled beds of igneous material. 



Manaia Hill Series (Jurassic)— 

Argillites, grauwackes, grits, and fine 
conglomerates. 



[The Torehine Series does not occur in 
Thames Subdivision.] 



Tertiary Volcanic Rocks of 
the " First Period " (Upper 
Eocene) (?)— 
Andesitic and dacitic tuff:<, breccias, 
agglomerates, and lava-flows. 



Tertiary Volcanic Rocks op the 
"Second Period" oe Beeson's 
Island Series (Miocene) — 
Semi-basic : Andfsitic and dacitic luffs, 
breccias, and lava-flows. 



Tertiary Volcanic Rocks op the 
"Third Period" (Pliocene) — 
Acidic : Rhyolitic tuffs, breccias, lava- 
flows. 



Pre-Pleistocbnb, Pleistocene, and 
Recent — 
Unconsolidated or poorly consolidated 
debris. River-terraces, river-beds, 
sea-beaches, drifting sands, talus 
slopes. 



Intrusive Igneous Rocks of Various 
Periods — 
Acidic : Rhyolite. 

Semi-basic: Diorite, porphyrite, ande- 
site, dacite. 



Tertiary Volcanic Rocks of the 
" Second Period " or Beeson's 
Island Series (Miocene)- 
Andesitic and dacitic tuffs, breccias, 
agglomerates, and lava-flows. 



Tertiary Volcanic Rocks of the 
"Third Period" (Pliocene) — 
Rhyolitic tuffs, breccias, agglomerates, 
lava-flows. 



Pleistocene and Recent — 

Unconsolidated or poorly consolidated 
ddbris. River-terraces, liver - flats, 
drifting sands, talus slopes, harbour 
muds, and swamp deposits. 



Intrusive Igneous Rocks op Various 
Periods — 
Diorite, porphyrite, andesite, dacite, 
rhyolite. 



• In Trans. N.Z. last., vol. xxxvi, 1903, page 443, Prof. Park remarks: ■■ Bocks belonging to the Jurassic system, in association with those ol tbe Trias, form the greater portion of the Tararua, Ruahiue, and Kaimanawa Mountains in the North Island ; and we have no reason to assume 
greater age for the slaty shales, sandstones, and grauwackes which form the floor of the Hauraki Peninsula." 

Geo, Bull. No. 10. [To face p. 128. 



129 



INDEX 



A. 



Page 



Acidic igneous rocks (see Tertiavv volcanic 

rocks of " First Period ") . . 15, 2(), 27, 44 

Acknowledgments . . . . 3 

Adelaide Claim (old) 91,92,128 

reef . . . . 70, 92, 93 

Adsorption . . . . . . 88 

Age of Tokatea Hill Series . . . . 20 

„ Manaia Hill iSeries . . . . 21 

Tertiary volcanic rocks of " First 

Period " . . . . . . 23 

Tertiary volcanic rocks of " Second 

Period " . . . . 25 

Tertiary volcanic rocks of " Third 

Period " . . . . . . 20 

„ intrusives . . . . . . 28 

Agricultural districts . . . . 2, 18 

Agglomerates (see Andesitic rocks and rhyo- 

litic rocks) . . 10, 19, 22, 23, 25, 20, 27 

Alabama Oeek . . . . . . 87 

Albion Claim (old) . . . . 90. 125 

Alburnia (see Old Alburnia and New Al- 
burnia). 
Hill . . . . 09, 70 

shaft .. 24.31.08,120 

Alfred Claim (old) . . . . . . Ho 

reef (Moanataiari Extende<l) . . 85 

„ (New Dart) . . . . . . 94 

All Nations Gaim (old) . . 90, 125 

„ Company . . 9, 90 

reef . . 70, 97, 98, 99. 101 

Alluvial deposits (see Recent and Pleistocene 

deposits) . . . . IC). 29 

flats . . . . 29 

Alteration of the volcanic rocks 3. 10, 18, 20-21. 34 

,. rocks of Manaia Hill Series . . 22 

Amalgamation |)rocess .. ..11,12 

Amorphous silica- . . . . . . 36 

Anchor or Ethel Reefs area (Hape Creek) . . 90 
„ „ description of the . . 94 

Andesites and andesitic rocks (nee Tertiary 
volcanic rocks of " First Period," " Second 
Period," and Intrusive rocks of various 
periods) . . 1, 3, Hi, 19, 20, 21. 27. 33. 72. 110 

.\ndesitic flow and breccia complex of 
Thames special area 08, 09, 80, 95, 111, 113-14. 
119-20, 122 
Andesitic gla.«s . . . . 28 

Ankerite .. 37, 41, 91 

Anticline . . 20, 22 

Antimonite . . 40 

Antimony . . . . . . . . 40, 57 

„ oxide . . . . 40 

,, oxy-sulphide . . . . . . 40 

., .sulphide (nee Stil)nite) . . 40 

Apakura Stream . . 00, 07 

Aragonite . . . . . . . . 30 

Area of Thames Subdivision . . . . 1 

Argentite . . . . . . 39 

Argillites . . 15, 19, 20-22, 28. 30. 08, 72 

Argosy Claim, description of the . . 03 

„ " Creek . . . . . . . . 03 

Arrindell Syndicate's Claims, description of 

the . . . . . . 88 

Arsenopyrite (arsenical pyrites) . . 38, 39, 40, 83 

Atlantic Claim (old) .". 90 

reef .. .. .. 90 

Auckland . . . . 1, 2 



Page 
Auckland adit (Arrindell Claim) . . . . 89 

Augite .. .. .. .. 23 

Augite-andesite . . . . . . 23, 26 

,, -diorite . . . . . . . . 28 

Auriferous areas of the Thames Subdivision 116, 117 
" .Auriferous Series " of volcanic rocks 22, 23, 119 
Australasian Crosscut (Thames Claim) .. 80 
Azuritc . . . . . . . . 42 

B. 

Balmoral level (Thames Claim) . . . . 80 

Barium . . . . 24, 37 

Barry's reef (Kurainii) . . . . 70, 95, 90 

Barytes (barite) . . 24, 37, 41, 80, 88, 89 

Basement sedimentary rocks 3, Ki, 20, 22, 30, 

08, 72, IK) 
Beach " lead " (Victoria Claim) . . 100, 107 

Beach " slide " or fault 10, 31, 32, 48, 70, 109, 

113, 114, 119, 120, 121, 122, 123 
Beach "slide," descrijition of the . . 31-32 

Becson's Island Series 10, 18, 23, 24, 25-2(i, 

33. 52. 54. 00, 04, 00, 07. 94, IKi 
Belemnites . . . . . . 21, 22 

Beletiiniten sp. . . . . . . . . 21, 22 

Bendigo Independent Claim (old) 85, 12(>-27 

Big Pump shaft (old) 32, 49, 10(), 107, 120, 

122, 125 
Biotite . . . . 27 

Bir<l-in-Hand Claim (old) .. 9, 110, 126 

reef 112, 113 

Hisnnith . . . . .39, .57, 80 

Black rcif (Scandinavian Claim) . . . . 03 

Block XXVI 1 (Thames) 29. 114, 115 

Blue reef (Southern (/ueen) . . 90 

Bonanzas of Thames . . 3, 42, 43, 70, 118, 120 
Bonanza Claim . . . . 08, 09, 77, 128 

,. description of the . . 77-78 

" Boom " (mining " boom " of 1895-98) . . 9 

Borehole, Kuranui-Caledonian ..9, 20, 21, 08, 

119, 123 
„ Victoria Claim . . 32, 123 

Boring (diamond drilling), value of . . 123 

Bornite . . . . . . . . 40, 76 

Breccia.s (xee .Vndesitic rocks and rhyolitic 

rocks) 15, 10, 19, 22, 23. 25, 20, 27, 34, 43 

Brecciated zones . . 33 

Bright Smile Claim (old) . . 9, 110. 112 

Broken Hill Claim (Waiomo) .. 38, 58-59, 00 
Building-stones .. .. .. 124 

Bullion Claim (Tapu) . . . . 52 

Buried forest . . . . . . 29 

c. 

Calamine . . . . . . . . 40 

Calcitc . . 30, 02, 72 

„ vein . . . . . . 54 

Caledonian Claim (old) . . 9, 96, 97 

Company (old) . . . , 9, 96 

Caledonian - Golden Crown bonanza 

9, 10, 97-98, 103, 105, 120 
Caledonian No. 1 reef .. 41, 70, 71, 80, 97, 98, 

1(»1, 102 
No. 2 reef . . 70. 97, 98, 101, 102 

No. 3 reef . . . . . . 97 

Cambria bonanza . . . . 102, 120 

Claim (old) . . 100, 102, 103, 126 

Gold-mining Company (old) 9, 100, 102 



9— Thames. 



130 



Page 
Cambria reef (see ^Vaiotahi-Cambria reef). 
Candlelight Claim (old) . . . . . . 87 

Cape Colville Peninsula . . . . . . 1 

Range . . . . . . 1, 17 

Capital — English capital invested . . 9, 14 

Capitalisation of Thames mining companies 14 

Carbonates . . . . . . . . 35, 40 

Carbonaceous beds . . . . 25, 26, 68, 122 

Carbonised wood . . . . . . 25 

Cardigan Claim (old) .. .. 108,110 

No. 1 reef . . . . 70, 71, 109 

Xo. 2 reef .. 70, 109, 112, 121 

Central Block of Thames special area 

16, 43, 48, 70, 114, 119, 120-23 
Central Italy Claim (old) . . 100, 126 

Cervantite . . . . . . . . 40 

Chalcanthite . . . . . . . . 40 

Chalcedonic quartz . . . . 16, 39, 124 

Chalcedony . . . . . . . . 36 

Chalcopyrite (see Copper-pyrites) 12, 36, 40, 72, 

76, 88, 89, 90 



66 

42 

24 

27 

63 

35, 37 

35 

10, 39, 64-66, 124 

41 

9,110,126 

92 

110 



Champion Claim (Puriri) 
Character of the country rock, and the ex- 
istence of productive zones 
Chemical analyses of andesites, dacites, pro- 
pyUtes 
,, rhyohtes 

Chicago Claim, description of the 
Chlorite 

ChloritLsation . . 
Cimiabar 
City of Dunedin reef 

„ London Claim (old) 
„ Manchester Oaim (old) 
York Qaim (old) 
Classifications of rocks of Hauraki Peninsula 

by previous writers (see Appendix) . . 19, 20 

Oimate . . . . . . . . 2 

Coal . . . . . . . . 26, 124 

„ for steam-power . . . . . . 13 

Coal-bearing strata . . . . 15, 124 

Coaly partings . . . . . . . . 16 

Coast-fine of Hauraki Peninsula within the 

Thames Subdivision . . . . . . 17-18 

Collarbone fault . . . . 31, 69, 70, 83 

Gully .. ..31, 69, 90, 113 

Colorado (old Comstock) Claim, Waiomo, de- 
scription of the . . . . 59 

„ ore, analysis of . . . . 59 

Comstock (U.S.A.) .. .. .. 46 

Claim (old), Waiomo . . 59, 124 

„ Creek (Waiomo) . . 56, 57, 59 

Concentration proces-ses .. .. 11, 12 

Conglomerates . . . . 15, 19, 21-22, 28 

Consolidation of volcanic rocks . . 18, 26, 35, 08 
ConsoLs Claim (old) . . . . . . 93 

Copper . . . . . . 10, 1 17, 124 

,, native . . . . . . . . 40 

„ -pyrites (see Chalcopyrite) 40, 41, 54, 55, 
57-58, 61, 74, 80, 91 
Cores of remnants of fresh andesite (see 

" Hard bars ") . . . . . . 35 

Coromandel . . . . . . . . 8, 38 

Subdivision 1, 15, 17, 18, 20, 22, 23, 124 
Correlation of reefs on each side of Moana- 

taiari fault . . . . . . . . 70 

Costs of mining . . . . 14, L17 

Country rock — its influence on the localisa- 
tion of ores . . . . . . . . 75 

Crateriform hollows . . . . . . 3 

Craters .. .. 3, 21, 23, HI, 120 

Crawford's Special Claim (old) . . . . 110 

Cripple CVeek (U.S.A.) . . . . 3, 36, 44, 47, 81 

" Critical levels " for deposition of ores . . 43 



Page 

Crown Mines, Karangahake . . 122 

Crown Prince Claim (old) . . 106 

Crown Princess Claim (old) . . 39 

Company (old) . . . . 108 

Crown reserve for pumping-station . . 110 

Crustification in veinstone . . 41, 76, 80 

CryptocrystaUine silica . . . . . . 36 

Cuprite . . . . . . . . 40 

Cure Claim (old) . . . . . . 103 

„ Company (old) . . . . 9, 103, 104 

„ reef . . . . 10, 104, 106 

Cyanide process . . . . . . 12 

D. 

Dacites and dacitic rocks (see Tertiary vol- 
canic rocks of " First " and " Second " 
Periods, and Intrusive rocks of various 
periods) 16, 19, 24, 26-27, 33, 68, 69, 72, 116 
Darby's reef . . . . . . . . 97 

Darwin Gold-mining Company (old) . . 100 

Dauntless reef . . . . . . 43 

Day Dawn and Norfolk Claim, description of 

the .. .. 71-74 

Claim 12, 13, 40, 41, 71, 74, 
75, 119, 128 
,, ,, Gold-mining Com 

pany . . 
,, „ ore — analyses 

„ „ reef 

Deadman's Point 
Deep Sinker Claim (old) 

,, shaft 

Depression of land (see Subsidence) 
Depth — influence of depth on ore-deposi 

tion .. .. .. 3, 42, 45, 118 

Detailed descriptions of mining areas and 

mining claims .. .. ...50-115 

Diehard \'alley : description of mining 

prospects 
Dioptase 
Diorites 
Disposition (general) of the rocks of Hauraki 

Peninsula 
Dives Claim (old) 

Dividends paid by certain Thames companies 
Dixon's ConsoUdated Claim 

„ description of the 

Dixon's No. 1 reef (Alburnia) . . 43, 70, 78, 79, 

82, 83, 120 
Don Pech-o Claim (old) . . . . 96, 100 

Downfaulted areas or blocks 16, 18, 30, 32, 114, 123 



Cross-courses 



effect on localisation 



. 34, 44 

of ores 

3, 42-43, 72 



n 




14 






72 






73 






1 


114, 


126 


114, 


115 



16, 30 



54^55 

40 

19, 27 

30 

92 

9 

72 

75 



Drainage of Thames mines 

Drifting sands 

" Dropper " veins 

Dunedin reef (see City of Dunedin reef) 

Duke's reef (Kuranui-Caledonian) 

(Una Hill) . . 43, 70, 

Duty (export duty) on gold 



. 11, 14 

19 

. 34, 45 

.73,119 

. 97, 98 
91, 92, 93 
9, 10, 13 



D\-kes (see Intrusives) 16, 17, 20-22, 25, 28, 29, 40 

E. 

Earth-movements (see Orogenic movements, 

Elevation, and Depression, of land) . . 16, 30 

EcUpse Claim, description of the . . 61 

„ reef (see Vulcan reef) . . . . 117 

Electrum . . . . 10, 37-38, 42, 53 

Elevations of the principal mine-workings of 

the Thames special area . . . . 125-28 

Elevation of land . . . . 15, 16, 30 

Enargite . . . . . . 40, 88, 89, 90 

Eocene (uppe-) volcanic rocks . . . . 19, 23 

Epidote . . . . . . . . 35 

Epsomite . . . . . . . . 37 

Erosion, suba 3rial . . . . . . 15 

Erubescite . . . . . . . . 40 



131 



Page 

Eruptive "' after-actions " . . . . Hi, 34 

Estuarine deposits . . . . . . 16 

Ethel Reefs (Jokl-iriring Company (old) . . 90 

Eureka Claim (old), Kuranui area . . 95 

Hill Claim (old) . . . . . . 100 

„ reef (Gtanui) .. .. .. 65 

Exchange Claim (old) . . . . - . 108 

F. 

Fame and Fortune Claim (old) . . 85-86 

Faulting . . . . 30, 34, 52, 55, 87, 109 

Faults (sec Moanataiari fault and Beach 

" slide ") 3, 16, 18, 32, 42, 43, 44, 70, 72, 107 

Faults, origin of . . . ■ ■ ■ 30 

,, normal and reversed 30 

„ effect on localisation of ores . . 43-44 

Felsitic rocks . . . . 15, 20-21, 28, 50, 08, 72 

Feldspars . . . . . . . • 23 

Ferguson Mining and Smelting Company 12, 58, 59 
Ferric oxides . . . . . ■ • • 23 

Financial conditions (Labour and tinancial 



conditions) 
Firth of Thames 



13 



" First Period " volcanics 



1, 2, 16, 17, 18, 29, 32, 

48, 61, 69, 70, 123 
15, 19, 22-24, 60, 64, 
67, 68, 116 
Fish .. .. .. 2 

" Flinties " . . 42, 43, 44, 91, 92, 93, 107 

Floors of counti-y carrying ores {see Zones). 

Flow structure . . . . 27 

Fogarty's Claim . . . • 90 

Folding of strata . . 15, 21 

— a main line of New Zealand folding 21, 34 

— Ruahine-Alpinc line of New Zea- 



land folding 

Fortuna Claim (old) 

„ <!ol(l-mining Company (okl) 

Fossils 

Foxes' reef (Thames Claim) 

Fuller's earth . . 

Future prospects of gokl-silver mining 

Future prospects of mining areas outside the 

Thames special area . . . . . . 117-18 

Future prospects of the Thames special area 118-24 
(n.) In the Upland block . . . . ll!»-20 

(6.) „ Central block .. ..120-23 

(r.) „ .Seaward block .. ..12:5-24 



33 
93, 128 

93 
. . 20, 21 

86 

37 
, .ll()-24 



G. 



Galena 36, 40, 41, 54. 55, 57-58, 61, 72. 74. 
(languc- minerals of the veins 
Garnets 

Gas (mine-gas). . , . 11. 47. 1 

„ „ analysis of 

„ -power plants 
Gem Claim (Waiomo) 

Genci-al description of the Thames Subdivi- 
sion 
,. geological features 
Gcnthite 

Gentle Annie Creek (Te Mata) 
Geological features (geijeral) of the subdivi- 
sion 
Geology of the subdivision, outline of the . . 
German reef (Una JJiH) 
Gibraltar reef . . . . ■ • 70, 

Gloucester Claim (old) . . 

Gold . . . . . . . • 

Gold-bearing reefs (principal) of Thames 

special area . . 
Gold duty . . . . . . 9, 

Gold- fineness of electnim . . 37- 

Gold-sUver output . . . . 10, 1 1 

„ „ diagram showing 

„ quartz veins . . 



(). 80 

36 

37 

20. 124 



47 
13 

38 

1-2 

2 

40 

51 

3 
15 

91, 92 

91, 93 

88 

37-39 

70-71 

10, 13 

■38, 53 

6. 118 

10 

3 



Page 

Golden Age reef 31, 35, 43, 70, 71, 84. 86, 87 

Golden Calf Claim (old) . . 100, 125, 120 

Golden Crown Claim (old) 96, 97-98, 103, 104, 125 

,, bonanza (see Caledonian - 

Golden Ci'own). 

Company (old) . . 9, 96, 103, 104 

lode (Caledonian Nos. 1 and 2) 95 

Golden Drop Claim, description of the 87, 127 

Golden Era shaft (Kuranui) . . . . 70 

Golden (;ate Claim (old) . . . . 106 

Golden (Jem Claim (old), Waiomo . . 60 

Golden Hill Claim, Manaia . . . . 51 

,, reef, Manaia . . 51, 116 

Golden Point Claim (old), Tapu . . . . 52 

reef, Tapu . . . . 52 

(iolden Run Claim (old) . . . . 108 

Gossans . . . . . . . . 42 

Gouge in fault- fissures . . . . 31 

„ or " dig " on walls of veins . . 34 

Graben of Firth of Thames . . l(i, 18, 29, 32 

Grahamstown . . . . . . . . 106 



Grauwackes 

Greenstone reef (.Arrindell Claim) 

Grits . . 

Groundmass of the andesites 

Gumtown 

Gypsum 



15, 19, 20-22, 36 
89 

. 15, 19, 21, 22 

24, 25, 27 

10 

37 



H. 



Hague-Smith reef 



70, 90, 91, 92, 93, 94 



Halcyon Claim, description of the . . 89 

Hand-in-hand Claim (old) . . . . 106 

Hansen's reef (Arrindell Claims) . . . . 89 

Hape CYeek . . 29, 30, 33, 39, 40, 67, (i9, 70, 

90, 93, lis 
Harbour muds . . . . 19 

■' Hard bars ' . . 35, 86, 96, 100, 1U9, 111, 121, 124 
Hastings Survey Ui.strict . . . . 1 

Hauraki Gulf . . . . . . 29 

Hauraki Mine, Coromandel . . . . 9 

Plains (.*ee Thame*-Piako Plain) 

1, 16, 17, 18, 27 
Peninsula . . . . 16, 17, 20, 21 

Hazelbank Claim (okl) . . 9(>, 125 

Heklfs Claim (old) . . . . 100 

,, reef (New Moanataiari Claim) . . 101 

Hcssitc . . . . . . 37, 38-39, 80 

High-level terraces (see Terraces). 

Hihi Stream (Kauaeranga) 

Hikutaia 

History of mining-development, Thames 

Hoisting 

Hokimai Creek (Kirikiri) 

Holocrystalline rock 

Homeward Bound Claim (okl) 

Hornblende-andesites 

,, porphyrite . . 

Hunt's (Shotover) bonanza 

„ „ Claim (old) 

,, Creek (Waikawau) 

„ reef (Shotover) . . 
Hyalopilitic type of groundma,ss 
Hydrothermal action 
Hy|X!rsthcne 



. . 29, 64 
2, 10, 27 
8 
11 
(>6 
. . 28, 69 
95 
23, 24, 26, 28, 69 
28 
.. 95-96 
95 
51 
. . 95, 96 
24, 25, 29 
3, 15, 16, 20, 22, 35 
24, 28 



andesites 



23, 26, 28, 29, 69 



I. 



Igneous rocks, section of report describing. . 22-29 

Imperial City Claim (old) .. .. 103 

reef .. .. .. 104-5 

Imperial Crown (old) Claim . . . . 106 

Increment of temperature with depth . . 4.5—46 

" Indicator " veins . . . . . . 44, 91 

induration of strata . . . . . . 21 

Industries at Thames . . . . . . 2 

InUers .. .. .. 23,25,117 



13-2 



Paige 
Inoccramus haasti . . . . 21 

Intersecting veins as inliueiiciiig localisation 

of ores . . . . . . 42-43, 105 

Interstratificd beds of igneous material . . 19, 20 
Intrusive rocks . . . . 3, 1 (i, 22, 50 

„ of various periods . . 19, 22, 27 

Inverness Claim (old) . . . . . . 9(i 

Iridium . . . . . . . . 39 

Irishtown . . . . . . . . 29 

Iron Cap reef (iSylvia Claim) . . 41, 42, 75 

Iron-foundries at Thames . . . . 2 

Isotropic material in rhvolites . . . . 27 

Ivy Claim (Una Hill) ". . . . . . 90 



J. 



Jasper 

Jerry's Cicek (\\ aiwawa) 
Jointing (columnar) 
Joker reef (Puriri) 
Junction Claim (old) 
Jupiter reef 



36 

M 

29 

(57 

il(i, 125 

91, 93, 94 



Lead sulphide (see Galena). 

Leaf-impressions 

Leucopyritc 

Leucoxene 

Lignite 

Limonite 



Jurassic rocks 3, 15, 19, 20-22, 28, 33, 36, 51, 08 
Just-in-time shaft . . . . 100, 103, 120 

K. 

Kahjkatea (white-pine) . . . . . . 3 

Kaimarama Stream . . . . 1,18, 23, 03 

,, Valley, descrii^tion of the mining 

prospects of the . . . . 63-64 

Kaiser Claim (old), Tararu . . . . 41 

„ reef (Sylvia Claim) . . . . 75 

KalgoorUe . . . . . . . . 81 

Kaolin . . . . . . . . 37 ] 

Karaka Creek . . 8, 31, 37, 39, 40, 05, 09, 86, 87, ; 
89, 90, 92, 110, 115 
ilines . . . . . . . . 24, 90 

Karangahakc . . . . . . 2, 39, 43 

Kauaeranga River 12, 17, 18, 25, 26, 28, 29, 33, 
30, 37, 39, 04, 116, 124 
Valley .. 25,29,67,116,124 

„ „ description of mining 

claims and prospects 64—66 
Kelly's reef . . . . . . . . 97 

Kermesite . . . . . . . . 40 

" Kindly " country or " Kindly sandstone " 

30, 42, 121 
Kirita Baj- (Coromandel Subdivision) 17, 21, 22, 28 
Kirikiri Mine . . . . . . . . 06 

Stream 17, 18, 25, 27, 29, 07, 116 

„ Valley : description of mining 

claims and prospects . . . . 66 

Kopu . . . . . • 2 

Kotoreputuai Stream (Puriri) . . . . 67 

Kuaotunu . . . . . . 30, 30, 42 

Kiuauui (Shotover) bonanza . . . . 95 

Kuranui Claim 24, 67, 79, 100, 114, 122, 125 

., description of the. . . . 95 

(old) . . . . 44, 95, 125 

Kuranui Company . . . . . . 95 

(old) . . .-. . . 9, 96 

Cieek.. .. .. 8,30,40,08 

Hill . . . . 42, 43, 70, 99, 122 

Kuranui-Caledonian borehole (see Borehole). 

Qaim 37, 39, 40, 46, 100, 

101, 104, 122, 125 

„ Claim, description of the 96-99 

Company .. 14, 119, 121 

shaft .. .. 121 

L. 

Labour and financial conditions . . . . 13 

Lapilli . . . . . . . . 26 

Lavas . . . . 15, 16, 19, 22, 23, 25-27 

Lead 10,117,124 

„ chloride . . . . . . . . 40 

„ native . . . . . . . . 40 



Page 

26 

..40 

35 

. . 25. 26 

42 

Literature dealing « ilh Thames (>oldtield . . 4—7 
Little Agnes reef (Sylvia) . . . . 75 

Liverpool Boys reef . . . . . . 87 

Loam.. .. .. .. 29 

Localisation of ore-deposits . . 3, 42-45 

London Claim (old) . . . . . . 108 

Londonderry Claim (old) . . . . 87 

Lone Hand section of May (^uecn Claim 90, 110, 126 
description of the . . . . . . 92 

Long-drive Claim (old) . . . . . . 96 

Company (old) . . . . 9, 96 

Look-out Rocks . . . . 36, 67, 87 

Loosely consolidated and unconsolidated 

debris . . . . . . . . 29 

Lord Nelson Claim . . . . 95 

Extended Claim . . . . 90 

No. 2 Claim . . 90, 128 

Lovvrie's reef (Scandinavian Claim) . . 63 

Loyalty Claim (old) . . . . . . 115 

reef (Pride of Karaka) . . 70, 91, 93 

Lucknow Claim (old) .. .. .. 110 

Lucky Hit Creek . . . . . . 88 

„ Gold-mining Company (old) . . 88 

reef .. .. .. 89 

M. 

Macadamising, rocks for . . . . 124 

Magnet Claim . . . . . . 40, 89, 127 

„ description of the . . . . 87-88 

Magnetite . . . . . . . . 35 

Magnolia Claim (old) .. .. .. 93 

Mahakirau Stream . . . . . . 63 

Mahara Royal area (Ta2)U), description of the 54 
reef . . . . . . 54 

Malachite . . . . . . 40, 42, 70 

Manaia Hill Series (see Jurassic rocks) 15, 20, 21-22 
Stream.. .. .. 20,22,23 

Valley .. .. .. 28, 116 

description of the mining prospects. . 50-51 
Manchester Claim (old) . . . . . . 89 

Mangakirikiri Stream . . . . 25, ()4— 65, 116 

Valley . . . . 64, 124 

„ „ cinnabar occurrences of 65 

Manganese-carbonate (see Rhodochrosite) . . 42 

,, oxides (see Wad) . . . . 41 

,, siheate (.see Rhodonite). 

Manganite . . . . . . . . 40 

Mangarehu Vallev . . . . . . 64, 65 

Manukau Claim (old) . . . . 97, 103 

„ Gold-mining Company (old) 9, 103, 104 

Maratoto . . . . . . . . 38 

Marcasite . . . . . . . . 39 

Maria Mine (old), Karangahake . . . . 39 

Mariner Claim (old) . . . . . . 108 

Mariners reef . . 70, 104, 100, 107, 108, 121 

Mary Ann shaft . . . . . . 104 

Marj' Helen reef (Arrindell Claim) . . 89 

Mata (Te Mata) Stream . . 18, 22, 25, 28, 124 

„ Valley . . . . . . 23, 116 

„ ,. description of mining prospects 51-52 

Matatoki Stream .. .. 18,25,27,110 

„ ^'alleJ^ : description of mining pro- 
spects . . . . . . 66 

Maumaupaki Moimtain . . . . . . 17. 25 

May Queen Qaim 24. 38. 39. 41. 44, 40, 48, 09, 

71, 121, 122, 125, 126 

„ description of the 110-14 

May Queen Gold-mining Company 99, 121, 122 

No. 4 reef .. .. 70, 112, 113 

„ north-west reef .. 70, 112, 113 



133 



Page 

May Queen Extended Claim . . 90, 128 

„ ,, description the 92 

Melaconite . . . . 40 

Mellite . . . . . . 37 

Men : number employed in mines . . 13 

Mercury . . ' . . . . 10, tili, 124 

Messengers Hill S2, 84, 119 

Metalliferous deposits of Thames other than 

gold-silyer yeins . . . . 124 

veins . . . . 33 

Metamorphism . . . ■ 20, 28 

Microcrystalline groundmass in yolcanic 

rocks . . . . . . 24 

Micropnecilitic <;roundmass . . 24 

Mill Creek (Ounaroa) . . . . 25, 26, 124 

Mine-waters, analyses of . . 49 

Mineralising agents in formation of Thames 

veins . . . . . . . . 34 

Mineralofiy of the vein-minerals . . . . 3(i-41 

Mineral-production . . 10 

Minerals, metallic . . 37-41 

,, non-metallic . . . . 3G-37 

Mining and treatment of ores 11 

Miocene volcanic rocks . . . . 19, 25 

Miranda . . . . . . 18, 29 

Mispickel . . . . . . . . 38, 39 

Moanataiari bonanza (No. 9 reef). . 101, 120 

Claim (old) 100 

., Company (old) (iec New Moana- 

taiari)" . . . . 9, 100 

CVeek . . 39, 81, 84, 85, 100, 118 

cro.ss.lode . . . . 43, 70, 84, 85 

„ Extended Claim, description of the 85 

fault iti, IS, 30, 31, 32. 44, 40, 48, 68, 

70, 71. 78, 79, 82, 84. 85. 80, ill, 94, 

95, 96, 90, 100, 101. ll:{. 114. ll.'i, 

119, 120. 121. 122. 123 

fault, <leseription of the 

,, downthrow of the 

No. 3 (All Nations) reef 

No. 9 reef . . 

tunnel 2(1. 37. 45. 4(), 



.. :{(»-31 
31 
101 
70. 101 
48. 60. 81. 82, 
84. 85, 8t). 87, 9t), 98, 100, 
119. 120, 121. 12.-). 127 

3.'). 8(i. !I6 



Valley 
Moa Mine (Te .\roha) .. 

„ reef (L'na Hill) 
Moehau (Coromandel Subdivision) 
Molybdenite 

Monowai Claim 36. 38, 39. 40. 41 

„ „ description of the 

tJold-niining Company . . 
Morning Star Claim (old) 
Motive power . . 

" Mottled " country rock 43, 65, 

Mount Zeehan Claim 

description ot the 
ore, analysis of the 
Mudstones 
Mus-sel, fresh-water 
Mclsaac"s Claim, Tapu (old) 
Creek (.Mahakirau) 
„ reef, Tapu 



39 

0. ill, it2. 126 

17 

41 

5.-), 124 

5t)-5!l 

13 

100 

12 

120 

40 

.)5-.-)6 



112 



. . 2t), 27 
2() 

.. 52-.-)3 

t>3 

52, 53, 116 



N. 

Nana reef (St. Hipiw) .. 70,113,126 

Nature and disposition of the vein fissures . . 43 

Negative movements of the strand-line . . 16, 18 
New .\lbumia Company . . 9 

New Dart Qaim 90, 128 

„ „ description of the . . 93 

No. 1 reef .. .. . . 91. !I4 

No. 2 reef .. .. 91,9.3,94 

New Moanataiari aaim . . 70, Oil, 100, 110, 121, 

122, 126 
„ description of the 99-103 



Pago 
New Occidental Claim . . . . 44, 90, 128 

,, description of the . . 93 

New Una Claim . . . . 90, 128 

description of the . . 92 

Nickel silicate (genthito) . . . . 40 

Nightingale reef (Scandinavian Claim) . . 109 
Nonpareil Claim (old) [now in Thames ClaimJ 85, 127 
,, (,'onipany (old) . . . . 87 

,, Claim (old) [now in New Moana- 
taiari Claim] .. 85, 100, 126 
Nonpareil Company (old) . . 9 
North Devon shaft (Albmiiia) . . 83 
North Star Claim (old) . . ill. 93, 128 
reef . . . . 01, 93 
North-west reef (May t^ueen) .. 70. 112, 113 
Norwegian Claim (old) . . . . 85, 127 

0. 

Occidental reef (see New Occidental) 70, 91, 93 
Officers connected with the field-work . . 3 

Ohinemuri . . . . 3t), 38 

Ohio Creek (lararu) . . 37, 67, tiS, 75, 117, 118 
Ohui . . . . . . . . 10 

Old Alburnia Claim 43, 78, 100, 119, 120, 126-27 

description of the . . 81-84 

Old IJeaih Claim (old) . . . . . . 108 

Old Big Pump shaft (see Big i'unip). 

Omahu . . . . 10 

Stream . . . . 18, 23, 25 

Valley 67 

Onehunga reef (scf Hague-Smith reef) . . 91 

Opal . . . . . . . . . . 3() 

Ophir Claim (old) . . 89 

Oro-doposits .. .. 16.42-45 

Ore-reserves, estimation of . . 14 

Ore sampling and a.ssaying . . 14 

Ore-shoots (fire Ore-deposits) . . . . 3, 42 

■■ Ore to ore " . . . . . . . . 43 

Orlando Claim (old) 85,127 

Orogonic movements (.str Karth-moxeiuents) 1,5 

Orthmlase . . . . . . 27, 28 

Otago Claim (old) 96,12.5,126 

( Itakeo Creek . . . . 22 

terrace . . 29 

( Itanui Consols Claim .. ()4, 118 

„ description of the .. 65 

Creek . . . . . . 25. 3!l, <i4-65 

-Mining Syndicate 13 

Otohi Crock . .' . . . . 29 

Valley : description of mining pro- 
spects. . . . . . . . 61 

Oturuturu Valley: description of mining 

])rospccts . . . . . . . . .54—55 

Ounaroa Stream (see Mill Creek) 1, 18, 64 

„ description of mining i)ro- 

s{)ects . . . . 64 

Outline of the geology and physiography of 

the Thames Subdivision . . . . 15 

Oxidation of vein.stone .. .. .. 48 



Ptuikihauraki Creek . . . . 51 

Paeroa 1, 2, 17, 18 

Papa (Te Papa) (Jully . . 91, 93, 94 

Papakai Mountain . . . . 17, 25 

Parawai (Thames) 94 

Paroquet Claim (old), Waiomo . . 5t), 59, (id 

description of the . . 59-60 

Creek . . . . 56 

Pearlspar . . . . . . 37 

Peaty material . . . . 29 

Periods of eruptive activity . . 2 

,, mineralisation . . 33 

Petrology . . . . . . 20 

„ of " First Period "" volcanics . . 23 



134 



Page 

25 

27 

28 

.. 38-39 

. . 15, 16 

.. 1, 18 

31, 110, 112 

24 

86 

2 

26 

29 

. . 2(), 28 

39 

29, 114 

19 

19 

20, 28 

17, 19 

27 



l(i. 



PetroJogy of " .Second Period "' \olcaiiics 
,, of " Third Period "" volcanics 

,, of intrusive rocks 

Petzite 

Physiogiaph\-, outline of the 
Piako River 

„ Claim (old) . . . . i), 

Pilotaxitic groundmass . . 
Pinafore section of Thames Claim 
Pine (white-pine, kahikatea) 
Pipes : mineralised pipes 
Plagioclase 
Plateau (rhjolitic) 
Platinum 
Pleistocene deposits 

„ and late Pliocene deposits 

,, and Recent deposits . . 

Pliocene rocks . . 

„ volcanics 
Plugs : lava plugs 
Point Russell Gold-mining Company {xcc 

Moanataiari Extended Claim) . . . . 85 

Point Russell section of the Old Albumia 

Claim {see Reuben Parr section) 82, 84, 100 

Population of towns and settlements . . 2 

Porph\Tite . . . . . . 19, 20, 27, 28 

Poverty reef . . . . . . . . 97 

Pre-Jurassic stratified rocks 3, 19, 20, 28, 33, 

120, 121 
■' Premier " flow andesite of Thames special 

area 68, 69, 70, 82, 85, 86, 95. 96, 100, 104, 

106, 109, 111. 114, 120, 122 
Prescott's reef . . . . . . 94 

Pride of Karaka Company (old) . . . . 92 

reef /. . . 43, 91, 92, 93 

Pride of PameU reef (ArrindeU C3aim) . . 89 
Prince Imperial bonanza (Victoria Claim) 

43, 107, 120, 122 

Claim (old) . . 31, 106, 122 

„ Gold-mining Company (old) 9. 106 

„ No. 1 reef (Mariner's reef) . . 107 

No. 2 reef 106, 107, 121, 122 

shaft . . . . 107, 109, 122 

., vein-system . . . . 71 

Prince of Wales reef (New Una Claim) . . 92 

Productive zones {see Zones). 

Propylite . . . . . . . . 23, 34 

PropvUtic alteration, or propvlitisation {sec 

Alteration) . . 3, 20, 23, 25, 26, 33, 34-36, 

42, 69, 82, 121 
Prospecting undertaken bj- the Survey . . 117 
Prospect Creek, Waiwawa . . . . 64 

Proustite . . . . . . . . 39 

Pug . . . . . . . . . . 37, 88 

Puhoi Creek . . . . . . 55, 60 

„ VaUey : description of mining i)ro- 

spects . . . . . . . . 55 

Pumice . . . . . . . . 27 

Pumiceous sands . . . . . . 29 

tuffs . . . . . . 26-27 

Pumps {see Thames-Hauraki and (Jld Big 

Pump). 
Puriri . . . . 2, 8, 

., Stream . . 
„ VaUey .. 

description of mining jirospects 



10. 

17, 



17, 66, 118 
18, 23, 25 
27, 29, 116 
.. 66-67 
Puru . . . . . . . . . . 2, 61 

„ Big Reefs Claim, description of the . . 61 

• „ Consolidated Claim (old), description of 

the .. .. .. .. 60-61 

„ Stream . . . . . . 18, 25, 60, 124 

„ Valley : description of mining pro- 
spects . . . . . . . . 60-61 

PjTargvTite . . . . . . 39, 83, 98, 101 

P'vroelastic rocks . . . . . . 22, 26 

PJTite 23, 35, 36, 39, 41, 42, 63, 72, 74, 76, 98 
P3Titic veinlets . . . . . . 42-43 



PxToxono-audesites 
Pyrolusite 



Page 

.23, 24, 26, 68, «9, 70, 96 

41 



Q. 



110, 
. !». 

"0, 



Quartz 

platy . . 

" sugary "" (saccharoidal) . . 
,, as phenocrysts . . 
Quartz-sericite rocks 
Queen of Beauty Claim (old) [now a .section 

of May Queeii Claim] 9, 39, 43, 46, 110, 

Queen of Beauty No. 1 reef . . 70, 112. 

„ shaft {see Thames-Hau- 

raki) 
vein-system 
Queen of Thames Claim (old) 
Queen of the May Claim (okl) 
„ reef . . 

.shaft.. 

R. 

Railway communication 

Rainfall 

Raised beaches 

Recent deposits 

Red Queen Claim (old) . . 

„ reef 

Reefs, quartz . . 

Regional earth-movements and faulting 
ReUanco Claim 

,, description of the 

Replacements . . 
Reticulated veinlets 

Reuben Parr reef . . 35, 43, 70, 

„ section of Old 

Claim 



36 

36, 42 

42 

24, 28 
20 

122 
121 



91, 126 
71 



114 

110 
112 
111 



16, 29, 30 
29, 114 
96, 125 

97 

3 

30 

127 

85 

36, 41, 42 

41 

84, 85, 86 

Albumia 

82, 84, 85 
Rhodochrosite . . . . . . 36, 40, 72, 74 

Rhodonite . . . . . . 36, 40, 72 

Rhvolites and Hnolitic rocks 2, 16, 17, 19, 20, 21, 

26-27, 36, 116 
River-fiats . . . . . . . , 19 

Rock-alteration connected with minerali- 

.sation . . . . . . . . 34 

Rocky Point . . 20, 22, 30, 68, 72, 119, 128 

„ level (May Queen Extended 

Claim) . . . . 92, 126 

Rover reef (New Dart) . . . . . . 91, 94 

Royal Oak Mine, Coromandel . . . . 21, 50 

Ruapekapeka Creek (Puriri) . . . . 29 

Ruby low level . . . . 31, 126 

Ruby silver (see PjTargyrite) . . 39, 83, 98, 101 

s. 

Sawmilling . . . . . . . . 2, 18 

Saxon Claim 47, 67, 69, 71, 99, 112, 121, 122, 125 
description of the . . . . 108-10 

Saxon Gold-mining Companv . . . . 121 

" (old) .. 9 

No. 1 reef . . . . 70, 109 

No. 2 reef . . . . 70, 109 

„ shaft . . . . . . 70, 122 

vein-system . . . . . . 71 

Scandinavian Claim . . . . . . 117 

,, description of the . . 62-63 

Scarp — fault-scarp . . . . . . 30, 32 

Sea-beaches . . . . . . . . 19 

Seaward block of Thames special area 

70, 119, 123-24 
" Second Period '" andesites {see Beeson's 

Island andesites) . . . . 22, 25-26 

Secondary enrichment . . . . 43, 45, 60, 117 

Selenite . . . . . . . . 37 

Semi-basic volcanic rocks {see Andesites, and 

Dacites). 
Sericite {see Propylitisation, and Quartz- 
sericite rocks). 



135 



Page 

Settler's Creek . . . . . . • • 64 

SheUback Creek . . 30, 08, (59, 70, 77, 78, 

81, 85, 95, 9(> 
Sheeted zones . . . . - . ■ . 33, 41 

Sheridan Claim (old) Tapu, description of the 52 
reef .. .. •• •■ 52 

Shortland 8,09,90,114 

Flat.. .. 31, 114, 115 

Shortland Flat Claim . . . .69, 91, 114, 126 

„ description of the . . 1 14-15 

Shotover (Hunt's) bonanza . . 96, 120, 122 

Claim (old) . . 8, 95, 125 

Company (old). . .. 9 

Creek ' 42, 43, 08, 95, 96, 122 
reef . . . . ■ . 70 

Siam level (Waitangi) . . . . . . 78, 79 

Siam reef (Waitanei) . . . . . • 81 

Siderito . . . . • • ■ • 35 

"SiUca" .. .. .. .. 37 

Silic60u.s sint-ers . . . . 10. 30. 04, 05 

Silicified wood . . 30 

Sais .. .. 22 

SQver.. .. .. •• •• 37 

,. (native) . . . . . • 39 

,. output of 10 

„ sulphides . . . . 38. 39. 58, 74 

Silver Crown Claim (old) . . 39 

„ reef (Watchman) . . . . 74 

Silver Queen Mine (Maritoto) . . . . 38 

Six-hundred -and-forty-foot level (" 040 ft. ' 

level) . . 45, 47, 48, 67, lOG, 122, 123 

36, 



119, 120, 121 
12, 124 

2 

34 

HI. 84, 120, 127 

43. 70, 82, 83, 84, 85 



" Slate.s " 

Smelting 

Snow 

Solfatarism 

Sons of Fre(«l()ra a<lit 

Sons of Freedom reef 

South British adit 114,115, 

„ Claim (old) 

Southern Queon Claim, description of tlui 9(1, 
" Specimen " stone 
Sphalerite {tee Zinc-blende). 
Spheroidal alteration and weathering 
Spherulitie structure 
Star of California reef 
Star of the South reef 
Step faults 
Stephenson's reef 
St. Hippo Claim (old) .. .. 110, 

„ reef {see Nana) 

Stibnite . . 40, 51, 04. !H), !)1. 9S, 101 

Stilbite .. .. .. 37 

Stock-work . . . . 41, 42, 84, 91, 93, 95 

Stones for buildiufr and macadamising; pur- 
poses 
Stoping 

Stream-development 
Structure of vein-material 

„ Tertiary volcanic rocks of 

" First Period " . . 
Tertiary volcanic rocks of 
" Second Period " 

„ Tertiary volcanic rocks 

" Third Period 
Subsidence of land 
Success reef 



12(i 

115 

128 

11 

23 
27 
73 
83 
10 
94 
120 
113 



124 
11 
18 
41 

23 

25 



Sulphide ore 

Summer Hill Claim 

Sunbeam Gully 
„ reef . . 

Sunken-river mouths 

Swamp deposits 

Sylvia Claim 12, 36, 40, 41, 42, 68, 
,, ,, description of the 

„ „ metallurgical notes 

„ reef 



10. 



of 

27 

. . 15. 29 

. . 43, 83 

12, 14, 119 

95 

72, 74, 77 

70, 72, 74, 128 

. . 16, 30 

19 

,72, 118, 119, 128 

.. 75-77 

77 

70, 75-77, 124 



1 . Page 

Table Mountain . . 3. 10. 17. 20, 28, 29, 04 

Range .. .. 17, 18, 27, 28 

Table of geological formations conijiared with 

those of previous writers {sec Ap])endix). 
Table of formations . . . . 19 

Taiioia . . . . . . 10 

River . . . . . . 17 

Survey District . . . . 27 

Tairua-Waihi Subdivision . . 2, 10, 20, 07 

Talisman Mine, Karangahake . . 43, 122 

Tapu .. .. 2. 8, 18, 38, 54, 117 

„ Stream . . 20, 22. 25, 36, 40 

„ VaUey .. .. ..116 

,, „ description of mining prospects 52 

Tararu .. .. .. 18,61,124 

,. Creek and Vallev 18, 24, 30, 37, 38, 40, 42. 00, 
02, 03, 07, 08. 09, 70, 71, 75, 81, 82, 118, 119 
„ Creek Valley above Ohio junction : 

description of mining prospwts . . 01-03 
,, Mines (Limiteii) (see Eclipse Claim). 
To Aroha . . . . . . 39 

Tellurides . . 12, 14, 37, 38, 80, 81, 119 

Tellurium . . . . 57-58. 74. 70 

Temperature . . . . . . 2 

Temperatures, underground . . . . 45 

Temple Bar Claim, description of th(^ . . 03 

Terraces . . . . . . . . 19, 26 

high-love! 10, 18, 29, 114, 115 

Tertiary eruptive activity . . 2, 15, 22 

Tertiarv volcanic rocks of " First Period " 

15, 19, 22-24, 33 

■ Second Period " 

Hi, 19, 22, 25-2() 

■ Third Period " 

10, 19, 22, 26-27 
Tetradymit. . . 39, 80 

Thames . . . . . . 2, 8 

Claim 24, 127 

,, description of th(< . . 8.")-87 

Thames-Coromandol coach-roatl . . 2 

Thames crosscut from Moanataiari tunnel 

8(>-87, 119, 127 

Deep-levels Consolidat«tl Claim 100, 108 

description of the 115 

Drainage Board .. 11 

l-'onishonr Dredging Company .. 12 

Thames-Hauraki pumping plant .. 9, 11, 14 

shaft .. 48, 49, 110, III. 113, 

114, 120. 121, 122,123 

Extended Claim (old) .. 114 

Thames-Piako Plain (^eeHauriki Plains) 1, 16, 17, 19 

Valley . . . . 1, 2, 18 

Thames River . . .. ..18,25 

Thames special area, — 

Des<-ription of the area 07 

Boundaries . . . . 07 

Oldest rocks . . . . 08 

Vein-bearing rocks . . . . 08 

Andesitic flow and breccia complex . . 68 
Non-brecciated andesite (" Premier " flow) 69 
Structural breaks . . 70 

Gold-bearing reefs . . . . 70-71 

Detailed descriptions of the mining claims 71-115 
Future prospects .. .. ..117-23 

Thames Survey District . . . . . . 1 

,, Talisman Company (old) {see Magnet 

Claim) . . . . . . 87 

Valley.. .. .. . . 1, 2 

Thickness of " First Period " andesitcs . . 15 

"Thousand-foot" (1,000ft.) crosscut. Cen- 
tral block, Thames ..121-22 
Timber — mine-timber .. .. 11 

Tilting of strata . . . . 15. 10, 27, 30 

Tinker's (iuUy . . . . . . . . 40, 71 

Titaniferous minerals . . . . . . 35 

Titles to mining lands . . . . . . 13 

Tokatea Hill, Coromandel . . , . 60 



136 



691*7 



Page 
Tokatea Hill Series 15, 16, 19, 20-22, 28, 50, 

52, (58, lie, 119 
'L'ookey's Claim (old) . . . . 106, 125 

Tonapah (I'.S.A.) .. .. ..3,46 

Topography of Thames Subdivision (see 

Physiography) . . . . . . 2 

Topographic features due to faulting . . 16, 30 

Torehine Series . . . . . . 15 

Trafalgar Claim . . . . . . 90 

Transylvania, Hungary . . . . . . 3 

Treatment of ores . . . . . . 11, 12 

Trenton Gold-mining Company (old) . . 100 

shaft . . . . ■ . . 69, 86, 100 

„ section of Moanataiari Claim 71, 121 

Tribute system . . . . . . 13 

Trichites . . . . . . . . 27 

Trigonometrical Section No. 1100 .. 17 

Tuffs {see Andesitic rocks, and Rhvolitic 

rocks) 15, 16. 17, 10, 20. 22, 23. 25, 26, 27, 34 

Turua . . . . . . . . 2, 29 

Twin Peak (Puriri) .. .. .. 27 

u. 

Una HiU 31, 42, 43, 69, 91, 110, lU, 115, 119, 123 
Una HUl and vicinity, description of the 

mining claims of . . . . . . 90-95 

Unconformities . . 16, 21, 25, 26, 123, 124 

Underground gases . . . . . . 47-48 

temperature . . . . 45—46 

water . . . . . . 48-49 

Unio auclclandicus . . . . . . 26 

Upland block of Thames special area 

16, 43, 70, 119, 120, 122, 123 



Vanguard Claim .. .. 91,110,126 

,, ,, description of the . . 115 
„ crosscut from Thames-Hauraki 

shaft .. .. ..113 

,, crosscut from Deep Sinker .shaft. . 114 

reef .. .. .. 70. 112, 113 

Vegetation . . . . . . . . 2 

Vein-bearing areas . . . . . . 3 

Vein fissures . . . . . . . . 33 

Veins, quartz . . . . . . . . 16 

„ metalliferous . . . . . . 33 

Ventilation of mines . . . . 11, 14, 47 

Victoria borehole (see Boreholes). 

Claim . . 104, 108, 109. 121, 122, 125 

,, ,, description of the . . . . 106-8 

„ Gold-minina Company . . 106-121 

reef . . ' . . " . . . . 107 

Victoria Claim (old), Manaia . . . . 51 

„ reef, Manaia . . . . 51, 116 

Volcanic rocks . . 2, 15, 16, 18, &c. 

,, vents {see Craters) . . 3, 15, 69 

Volcano . . . . . . . . 3, 69 

Vugs . . . . . . 24, 41, 58 

Vulcan Claim (old) . . . . . . 61, 62 

„ reef .. .. .. 61, 117 

w. 

Wad . . . . . . . . . . 41, 72 

Wade reef (Thames Qaim) . . . . 87 

Wages paid for mining-work . . . . 13 

Waihi .. .. .. .. 2,42 

„ Mine .. .. .. .. 9 

Waihoanga Creek . . . . . .'?21, 22 

Waihou Survej' District . . . . . . 1 

Waikato .. .. .. .. 2 

River.. .. .. .. 29 

Waikawau . . 2, 17, 18, 21, 22, 28, 29, 51 

,, Valley : description of mining 

prospects . . . . . . -] 51 

[:G7 



Waimahoo Creek 
Wainora Creek 
Waiokaraka Gull}' 

,, volcano 

Waiomo 

,, Stream 



Page 

26 

26 

29, 69, 120 

69 

2, 12, 18, 36, 40, 54, 55, 117 

18, 28, 60 



,, Valley : description of mining pro 

spects . . . . . . 56-60 

Waiotahi bonanza .. 10, 105-6, 107, 118, 120 

Waiotahi-Cambria reef .. 31, 34, 41, 70, 71, 79, 

86, 97, 101, 102, 103, 104-5, 107, 120, 121 

Waiotahi Claim or Mine. . 10, 12, 37, 44, 46, 71, 86, 

99, 100, 102, 103, 108, 121, 122, 125 

„ Claim, description of the . . 103—6 

„ (old) .. .. ..103 

„ Gold-mining Company . . 9, 104, 121 

Creek 31, 81, 85, 86, 87, 100, 103 

,, foot-wall dropper . . . . 104 

No. 5 reef . . . . 104, 105 

VaUey .. ., .. 31 

Waipukapuka Creek . . . . . . 54 

Waitangi Claim 12, 36, 37-39, 40, 41, 78-81, 

96, 118, 119, 128 

,, „ analysis of ore-concentrates 80 

,, „ description of the . . 78-81 

Gully .. .. .. 70 

reef " . . . . . . 70, 96, 120, 124 

Waitemata Claim (old) . . . . . . 100 

Waiwawa River 1, 18, 25, 28, 29, 33, 64, 116, 124 
„ Valley : description of mining pro- 

spects . . . . . . 64 

Wallace's reef (New Moanataiari) . . 101 

Washoe (U.S.A.) .. .. .. 3 

„ amalgamation process . . . . 12 

Watchman Claim 12, 40, 41, 42, 72, 73, 75, 118, 128 

,, ,, description of the . . 74-75 

(WindfaU) reef . . 70, 74, 75 

Water-supplj' . . . . . . . . 2, 12 

\Vater, underground . . . . . . 42 

^Veathe^ing . . . . . . . . 27 

West Coast Claim, description of the 87, 127 

We Three Claim (Omahu) . . . . 39 

Weymouth Claim . . . . . . 90 

Whakarewa Stream . . . . . . 22, 51 

WTialebone Creek . . . . . . 36 

„ Valley : description of mining 

prospects . . . . . . 54-55 

\\Tiangaiterenga Stream . . . . . . 64 

Wharehoe Stream . . . . 25, 27, 116 

,, Valley : description of mining 

prospects . . . . . . 66 

Whau : section of Old Alburnia Claim 83, 127 

(Old Whau) Company (old) . . 9, 82 

Wheel of Fortune reef . . . . . . 97 

Whitianga Estuary . . 1. 25, 26, 63, 64, 124 

Harbour . . . . . . 17, 18 

Windfall reef (*"ee Watchman). 

Witherite . . . . . . . . 37 

Wonder Claim (old) . . . . . . 40 



Young American reef 
Young Queen Claim (old) 



97 
110, 114 



Zinc .. .. .. .. 10, 117, 124 

,, carbonate.. .. .. .. 40 

„ (native) . . . . . . . . 40 

Zinc-blende . . 36, 40, 41, 54, 55, 57-58, 61, 72, 
74, 76, 80, 88, 89, 90, 91, 98, 107 
Zones : Kuranui - Queen of Beaut}- or 
Kuranui - Prince Imperial productive zone 

42, 43, 96, 98, 102, 103, 106, 110, 122, 123 



By Authoriky: John Mackay, Government Primer, Wellington 




University of 
Connecticut 

Libraries 



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